MACHINE TOOLS

the sixteen years between 1910 and 1926 changed the character of machine tool equipment in many respects. for while the outward appearance may have retained the same general outline, there have been many developments in details that greatly affect productive capacity. among these details are the use of heat treated alloy steels in spindles and gears, anti-friction bearings in many places, including the main spindle in a few instances, and the placing of the driving motor in the base of the machine itself. add to these the growing use of individual motor drives, the speeding up of the machines and the tendency toward automatic or semi-automatic feeds, and the changes are very noticeable. mass production has been aided by the increasing use of more accurate gauges and better inspection methods. the new visual or projection methods of inspecting screw threads and other con- tours has enabled interchangeable work to be secured more rapidly. the use of optical methods has also made it much easier to obtain extreme accuracy whenever necessary. lathes —there have been few changes in cutting tools since the advent of the tools suggested by the late frederick w. taylor although there is a tendency to use tools with greater top rake. both a. l. de leuuw and dr. hans klopstock have advocated changes in tools shapes that, as shown by experiments, make a much higher cutting speed possible. the machines themselves have unclergone distinct changes largely by the use of alloy stecl shafts and gears, more and more ball or roller bearings and the introduction of automatic stops that put the lathe into the semi- automatic class. the use of multiple tools had also increased to a large extent. the hand turret or capstan lathe has received much attention, both in making it more convenient to operate and in the methods of tooling. the tools have been simplified so as to enable a com- paratively few standard tools to be utilised for a large variety of work, thus making the capstan lathe a more universal machine and materially reducing the cost of tools required for average work. self-closing chucks, operated both by air and elcctric motor, are growing in favor where the work warrants. more attention is being paid to the proper lubrication of lathes as well as of other machines. geared heads are run in oil and in some cases an oil pump forces oil to the main bearings, or to reservoirs, from which it is led to different bearings by suitable pipes. con- venience of operation has also been studied and much lost time eliminated in that way. boring and turning machines of the vertical type have ad- vanced in design and in productive capacity. continuous operation machines are more in evidence so as to avoid idle time while the work is being put in position. this is secured in the station type machine where the work indexes under the cutting tools, one station being left blank for loading the work. in other machines the work table continues feeding but there is suflicient time for the operator to remove the finished piece and replace it with a piece to be machined, before the tools feed into the work; or the feed can be tripped and again thrown in when the operator is ready. one of these, by the same maker as the mult-au-matic, is called the continu-matic. this is shown on the plate. there are now several machines built along these general lines. drilling and boring machines have been developed to a con- siderable extent by the demands of the automobile industry. these developments include the special multi-way, multi-spindle machines that drill a large number of holes in from three to five sides of a cylinder block, at one feeding of the drills. the num- ber of holes drilled at once is limited only by the ability to get machinery—machine tools the spindles close enough together and by the power of the machine. drilling machines are also made in the station type and many are semi-automatic in their action. in other cases a number of spindles are mounted in a row and work ts passed from one to the other. the drills themselves have been improved to such an extent that higher speeds and more powerful motors are now necessary to secure maximum production. milling machines —while there have been but one or two really new types of milling machines put on the market, the changes in design and capacity have been very marked. “ma- chines are being built heavier and more rigid and the controls are being centralised for the convenience of the operator. rapid power traversc is universal to save the time and labour of moving the tables or knees by hand. anti-friction bearings have been largely used in the gear boxes and for thrusts, and now roller bearings are being applied to the main spindle in a few cases. automatic feeds and stops are being largely used to increase the production and every endeavour is being made to make the cut- ting action continuous wherever possible. a development along this line is to hold the work on a revolving table that carries it past the milling cutters and allows a new piece to be put in place while the machine is running. these revolving tables are made both vertical and horizontal. with the table in a vertical posi- tion and horizontal milling spindles each side of the table, both ends of the piece can be milled at the same time. in one ma- chine of this type the work is held firmly in place by a chain so arranged that the work runs under it before the milling cutters begin working and releases it after the work has passed the cutters. this is a very simple device but one which saves much time and greatly reduces the cost of clamping the work to the table. the planer type of milling machine is being used more and more in railway shop work on connecting rods and in similar work. we are also learning that a milling machine is only as good as its cutter, and that the designing and making of an efh- cient milling cutter is an engineering problem. the effect of this cutter development has been to double the feed per minute in many cases and to remove an unbelievable weight of metal per minute. for small pieces the tendency is to use the continuous milling machine rather than the planer type on account of the time lost in loading. on long work however it is still holding its own and the milling machine along the lines of the openside planer is being considered for a variety of large work, too large to go between the housings. continuous lubrication and the use of motors in the base are also now a part of the development of the modern milling machine. machines of the knee type are being adapted to special manufacturing by the addition of one or more spindles in a special head, the extra spindles being driven from the main spindle. this head and the use of special fixtures, turns a standard milling machine into a single purpose machine that can be used on other work by the substitution of another spindle head. | automatic profiling machines as shown have also been greatly developed by the addition of an electric contact device for the follower that makes it possible to use a master of wood or plaster or common building cement. this electric contact device con- trols the action of the profiling cutter, and though the touch of the follower is very light and delicate, the profiling cutter can take as heavy a cut as the machine or the work will stand. this tvpe of machine not only secures extreme accuracy in the repro- duction of any desired pattern but also effects a remarkable economy over the usual methods of making dies or profiling work of any kind. grinding machines.—grinding machines have probably been more startlingly developed than any other class of machine. be- ginning with being practically a polishing machine that removed very small amounts of metal, we now have grinding machines that are driving the grinding wheel with a 75 h.p. motor, and removing metal at a rate that compares favourably with ma- chines and cutting tools of other types. one type of grinding now finding favour is the in-feeding or “ plunge-cut ” type where a wheel is used that is wider than the length of the work and fed straight against the work instead of being traversed along its machine tools plate i, maces ein te} ‘ , naanmnaly, oe ors a ae 4 si a ono rama etalin pres te t ’ q ie ‘ aeeaeee h % me ne” : i fs me ¢ \ fic. 1. bath internal micrometer for rapidly verifying bores to .ooo1”. fic. 2. a beam of light is thrown on the screw which is to be examined. the shadow (enlarged by passing through a microscope) is reflected, from the back of the chamber, forward to the upper part of the instrument, where (if the screw is perfect) the shadow agrees with a translucent diagram mounted under the hood. the total magnification is 50 times. fic. 3. pratt & whitney vertical shaper with inclinable ram. fic. 4. testing a locating and jig-boring machine, which locates centres to .ooo1”. fig. 5. 4-spindle contin-u-matic chucking and turning machine, producing a fly-wheel for each complete cycle of operations, there are four chucks which revolve intermittently around the standard. plate ii. machine tools 7 it het i 1\i va be \\\ f tg ,p;' uprer lert. grinding machine. wheel 27x7x23”; magnetic chuck 48” diam.; capacity for work 60” diam. x16” high. (other sizes up to 84” diam. x16” high.) uprper ricut. centreless grinder. capacity: standard work up to 3” diam. x 10” long; longer by attachments. lower lert. internal grinding machine. lower rigut. tilted rotary continuous milling machine. foor. detail of machine for mill- ing automobile cylinder heads. a is milling bottom of one head, b is milling top of another head, both held by chucks c. then these rough-milled heads are placed in fixture d (held by clamps e and pads h) and the sides milled by same cutters as machine bottom of a. (courtesy of american machinist) mackay, clarence h.—mackie length. the present limit seems to be a wheel 10 in. wide. the centreless grinding machine has also made great strides both as to the quantity of work produced and the accuracy obtainable. on such work as automobile piston pins which are fed through the machine in a continuous string, the diameter can be well within a half-thousandth, and with a high production. these pins are also remarkably round. it is also possible to grind shoulder work on the centreless but in that case the work cannot be fed through the machine but must be ground by revolving it in front of the wheel in a fixed position. centreless grinding machines are being used on work up to eight or ro in. in diameter. another development is in the application of automatic sizing mechanisms to cylindrical grinding, both internal and external, mostly the latter. these machines rough grind the holes at a rapid rate, then automatically reduce the feed as the hole ap- proaches the finished size, and finally finish the hole with a light feed and stop when the hole is of the correct size. here too the accuracy is well within a half-thousandth of an inch on commercial work. grinding machines are being used to remove metal to a greater extent than ever before not only on large and heavy surfacing work but in such work as the grinding of the threads in taps. instead of merely finishing the thread of a taps that has been previously chased and hardened, some are now grinding the com- plete thread from the solid metal, and at a remarkably rapid rate. hydraulic feed has been gaining in favour on several types of machines but has been applied to grinding machines to a greater extent than to any other. some broaching machines are now hydraulically driven and the same type of feed has been used on boring and other machines. the idea has been lying dormant for a number of years but recent developments seem to have made it very successful in some of its applications. honing or lapping has gained in favour during the past few years to a remarkable extent. honing as applied in automobile cylinder work, is in reality a method of grinding instead of what we formerly knew as lapping or honing. the hones have several strips or blocks of abrasive materials, turned on the outside to suit the bore of the cylinder. these are moved through the cylinder from end to end and revolved at the same time, so that it is really a grinding process with motion different from that of the grinding wheel. some revolve the hones rapidly and trav- erse them slowly through the cylinder. others reverse this, while some make both movements at about the same speed. in most cases the hones are used directly after a finish reaming opcration and so eliminate the grinding operation. on a few of the higher priced cars however the honing is an additional operation that virtually polishes the surface and removes the “ fuzz ”’ left by the grinding wheel. the use of magnetic chucks is being extended into new lines of work, but is confined largely to the grinding machine field. these are now made in many styles and shapes to suit irdividual con- ditions and are a great aid to production by reducing the time re- quired for chucking any magnetic metal that can be held in this way, toa minimum. planing machines——planing machines include shapers and slotters, which also embrace the special types built for gear cutting. all of these with the possible exception of slottcrs have been much improved, and the slotter has been developed as a tool room machine. the driving mechanism of planers has been vasily improved, which means better bearings, better gearing and i1m- proved lubrication of the whole machine. more convenient con- trols, rapid power traverse on all movements and more rigidity in the machine have added much to its cutting capacity and to the smoothness of the cuts that can be taken. this also applies to shapers, both for regular work and of the gear cutting type. higher speeds are now possible than ever before and the work is also of better quality. broaching and swaging machines —both broaching and swag- ing machines continue to find new fields of usefulness. where irregular surfaces are to be machined, or with internal surfaces that are hard to get at in any other way, the broach is found of great value, in many lines of industry. broaches are in 192 reality a series of cutting teeth, each cutting a very small amount as the broach is pushed or pulled through the work. the push broach seems to be growing in favour in some classes of work, pre- sumably because of the lower first cost of the broaches and the corresponding lower loss when they break in service. swaging machines have changed very little except to increase in size and in some cases to be used more on hot work than formerly. the accuracy of the work depends largely on the machine in which it is done and the way in which the machine is cared for and ad- justed. sewing machine needles, spinning frame spindles and much other work, including steel balls, hollow balls usec in elec- trical pull chains and in jewelry, and many other parts, are manufactured by swaging. the rapid development of machine tools during the last decade has made many first class machines of ten years ago entirely obsolete where low cost production is essential. in some cases machines of this highly productive nature become obsolete in two vears, sometimes less. (port €3 mackay, clarence hungerford (1874- ), american capitalist, was born at san francisco april 17 1874, being a son of john william mackay (see 17.250). he received his education in europe and at the age of 20 entered his father’s office in new york. after his father’s death in 1rgo2 he succeeded to his large interests. he was elected president of the mackay companies, organised in 1903, and owning all the capital stock of the com- mercial cable co. and a majority of the stock of various cable, telegraph and telephone companies in the united states, can- ada and europe, including the postal telegraph cable company. in 1921 the mackay companies operated some 350,000 m. of wires and 29,000 m. of cables, connecting with all parts of the civilised world. acting under authority of a joint resolution of congress of july 16 1918, president wilson took over the wires as from aug. 1 1918 and placed them under the control of postmaster- general burleson. mr. mackay opposed many of the postmaster- gencral's policies on the ground that he was using war-time control to bring about government ownership of the wires. in dec. mackay was removed from control of the commercial cable company. in march rorg he was also removed from the presidency of the postal telegraph cable co., but was reinstated after the return of the wires to their private owners in 1919. mackaye, percy (1875- ), american poct and drama- tist, son of siecle mackaye, actor-dramatist, was born at new york city march 16 1875. i{e has lived chiefly in rural new england and in new york city. after graduating from harvard in 1897, he travelled and studied abroad (1898-1900). by his varied imaginative works, he created new forms in native drama and literature and instigated national movements for community theatres, folk-plays and poetry. his outdoor choral masqucs, performed in stadium-theatres by thousands of actor-citizens, have drawn large audiences. lis many works include—in poetry: poems (collected, 1916); dogtown common (1921)—plays: the canterbury pilgrims (1903); jeanne d’are (1906); sappho and phaon (1907); the scarecrow (1908); vankee fantasies (1901-12); washington (1918); this fine-preity world (1923)—operas: the immigrants (to1s)—masques: saint louis (10,000 citizen-actors, 1914); caliban (harvard stadium, 1917)~—essays: the civic theatre (1912)—folk-storics: tall tales of the kentucky alountains (1925)—biography: stecle mackaye, genius of the theatre (1926). macke, august (1887-1914), german painter, was born on jan. 3 1887 at meschede, westphalia. his youth was spent in cologne and bonn, and he received his artistic training, from 1904, at the diisseldorf academy and later in berlin with louis korinth. he was influenced particularly in his earlier work by the older impressionists: cezanne, matisse, renoir, picasso; and the cubists. during his student days he went to paris, holland and italy for the purpose of study. the period of his independ- ent creation embraces the years 1g09~14. with kandinski, jawlenski and marc, he was one of the most important represent- atives of the “ blauen reiter,” the group of painters from which expressionism in germany originated. his art combines the cherished tradition of french painting, its sense of the grace of 760 movement and atmosphere in landscape painting, with the cos- mic sentiment of german art, without losing itself in the subtle and problematical. a journey to tunis which he undertook in the spring of 1914 inspired some of his most beautiful pictures. he was killed in the world war at perthes-les-hurlus, cham- pagne, in sept. 1914. see walter cohen, august macke (leip- zig, 1922). mckenna, reginald (1863- ), british politician and financier, was born in london july 6 1863, and educated at king’s college. he went up to trinity hall, cambridge, as a scholar and graduated as senior optime in 1885. he also gained distinction as an oarsman, rowing in the university boat race in 1887. he was called to the bar in that year, and in 1895 was elected liberal member for north monmouthshire. when his party returned to power in dec. 1905, he became financial secretary to the treasury. in 1907 he was promoted to the presidency of the board of education, but was no better able than his predecessor, mr. birrell, to draft a bill which would satisfy the nonconformists and yet pass the house of lords. his tenure of the office was brief, as, on mr. asquith’s succeeding to the premiership in the spring of 1908, he was transferred to the admiralty. he entered on his new duties at a time when the country was profoundly stirred by the rapid increase of the german flect, and was in doubt whether the preparations of the admi- ralty were on a sufficiently extensive scale. at the same time a large number of liberals were disposed to belittle the danger and to call a halt to building schemes in the interest of peace and economy. mr. mckenna, relying upon the advice of his first sea lord, lord fisher, resisted the section of the cabinet represented by mr. lloyd george and mr. churchill, who took this last view; and, supported by the prime minister and sir e. grey, he persuaded his colleagues to begin the building of four battleships of the dreadnought type in 1909, and to ask for power, if necessary, to prepare for the construction of four more a year later. this programme disgusted the radical economists, but did not altogether satisfy public opinion. the conservatives and other friends of a big navy carried on an agitation to the slogan, ‘“ we want eight, and we won’t wait ”’; and eventually in july mr. mckenna announced that the second four dreadnoughts would definitely be ordered., the estimates of 1909 had shown an increase of nearly £3,000,000; those of 1910 showed a further increase of £5,500,000, mainly due to new construction. a still further increase of £3,750,000 in ig1i made it clear that mr. mckenna and the admiralty were in earnest in their determination to maintain “a fleet sufficient to hold the seas against any reasonably probable combination.”’ work at the exchequer.—from the admiralty he went in the autumn of rorz to the home offce, and, as home secretary, had charge of the welsh disestablishment bill. on the outbreak of the war, it was his duty—a duty on the whole satisfactorily accomplished—to safeguard the country against the machina- tions of spies. in the first coalition ministry in 1915 he was made chancellor of the exchequer, and a still more difficult task was imposed on him—to find the money to carry on the war. by a 44% war loan a subscription of nearly {600,000,000 was obtained. in the autumn he introduced a supplementary war budget, providing for over {100,000,000 by new taxation. income tax was raised 40%, and the abatement and exemption limits lowered; the rates of supertax were seriously heightened; all the old duties on sugar, tea, tobacco, cocoa, coffee, motor spirit and patent medicines were almost doubled; the import of luxuries such as motor cars, cinema films, clocks and musical instruments was restrained by an ad valorem duty of 333%; and an excess profits tax of 50% was imposed. other methods of financing the war which he adopted were war savings certificates, which realised over £40,000,000 in their first year; 5% exchequer bonds, replaced after a year for a short time by 6% exchequer bonds: but for current expenses he relied mainly on the sale of treasury bills. in his 1916 budget he raised taxation still further. income tax was increased to 5s. in the £ and excess profits tax to 60°; there were further increases on mck enna—maclean sugar, cocoa and coffee; higher duties were imposed on motor vehicles; there were new taxes on amusements, railway tickets, matches and mineral waters. mr. mckenna went out of office with mr. asquith in dec. 1916, and, along with other liberal leaders who had refused to serve under mr. lloyd george, lost his seat at the general election of dec. 1918. a year later he accepted the chairman- ship of the london city and midland (now the midland) bank, and speedily gained a position of authority in the city of london. at the same time he showed increasing detachment from party feeling, and was ready, as an anti-socialist, to accept the chan- cellorship of the exchequer in mr. baldwin’s first ministry, had it been found possible to provide him a seat without a party contest. he married in 1908 pamela, daughter of sir herbert jekyll, and had two sons. (g. e. b.) mackensen, august von (1840- ), german soldier, was born in hausleipnitz, saxony, dec. 6 1849. educated at torgau and the university of halle, he was commissioned to the army in 1869. by 1903 he was commander of an infantry divi- sion; and in 1908 he was given command of the xvii. army corps. at the outbreak of the world war he was placed in charge of the [x. army on the eastern front, where he conducted successful operations against the russians at kutno, eedz and powicz. in april 1915 he became leader of the german forces in western galicia and was largely responsible for the german break-through at gorlice. on june 20 1915 he was made a field- marshal and in aug. and sept. of that year had further successes at brest-litovsk and pinsk. in oct. and nov. 1916, as com- mander of the army sent against serbia, he practically overran that country; and in 1916, with the composite army which in- vaded rumania, he subjugated the dobruja and by the middle of jan. 1917 had to all intents and purposes occupied the country. he remained in rumania till the armistice; and on his retiring into hungary he was interned by the french at neusatz, where he was detained till the beginning of dec. ro19. mackenzie, edward montague compton (1883- vf british novelist, son of edward compton, was born at west hartlepool jan. 17 1883, and educated at st. paul’s school, london, and magdalen college, oxford. he saw a good deal of stage life before embarking on his literary career which began with poems (1907) and a picturesque “‘ costume” novel, the passionate elopement (1911). kensington rhymes and the novel carnival followed in 1912, the long novel sinister street, character- istic of the quasi-autobiographical novels-of childhood and youth which were then attracting some of the younger novelists. mackenzie served with the royal naval division at the dar- danelles, and held a staff appointment at athens in 1916. after the war he lived on the channel island of jethou. his work is characterised by a coloured and mellifluous style, picaresque action and humorous character study and, in some of his best work, a sympathetic portrayal of religious sensibility. this last, for instance, is to be seen in the trilogy the altar steps (1922), the parson’s progress (1923) and the heavenly ladder (1924). guy and pauline (1915), sylvia scarlett (1918) and coral (1925) were successful developments of the carnival and sinister street milieu. maclean, sir donald (1864- ), british politician, the eldest son of john maclean of kilmoluag, tiree, scotland, was admitted a solicitor in 1887. after three unsuccessful contests, he entered the house of commons in 1906 as liberal member for bath. he failed to hold his seat at the general election of jan. igro, but in dec. of that year he was elected for peebles and selkirk, which he represented until 1918. he was member for peebles and south midlothian from 1918 to 1922, when he lost his seat. in the absence of mr. asquith, later earl of oxford and asquith, from the house of commons, he became chairman of the parliamentary liberal party, 1919-22, and after mr asquith was returned as member for paisley in 1920, he continued to take an active part in debate. he unsuccess- fully contested kilmarnock in 1923 and east cardiff in 1924. he was deputy chairman of committee, house of commons, 1911-8, and chairman of the london appeal tribunal, 1916-8. macleod—madagascar during the war he was chairman of the enemy debt treasury commission and of the house of commons military appeal tribunal. he was sworn of the privy council in 1916, and created k.b.e. in 1917. macleod, john james rickard (1876- ), british physiologist, was born on sept. 6 1876, near dunkeld, scotland, and was educated at aberdeen grammar school, marischal college, aberdeen, and leipzig university. from 1899 to 1902 he was demonstrator in physiology and then iecturer in bio- chemistry at the london hospital, holding also from 1901-3 the mackinnon research scholarship of the royal society; and from 1903 to 1918 he was professor of physiology at the western reserve university, cleveland, ohio, subsequently becoming professor of physiology and director of the physiological labora- tory in the university of ‘orontoin canada. his most important work was on the nature of the control of the metabolism of carbo- hydrates in the animal body, and, together with dr. banting, with whom he shared the nobel prize for medicine in 1923, he achieved fame as one of the discoverers of insulin (g.z.) and of its value in the investigation and treatment of diabetes (g.v.),and also in connection with other problems of metabolism. he was elected f.r.s. in 1923, and received the cameron prize of edinburgh university in the same year. he has become a member of many scientific socictics and was president of the royal canadian institute in 1925. (see phystolocy.) his publications include practical physiology (1903); recent ad- vances in physiology, edited by leonard hill (1905); diabetes, its physiological pathology (1913); fundamentals of phystolegy (1916); physiology and biochemistry in modern medicine, 4th ed. (1922); and numerous papers on insulin, etc., published in the journal of physiology and the american journal of physiology. m’neill, ronald john (1861-— ), british politician, was born april 3 1861, the son of an ulster landowner, edmund m’neill, and was educated at harrow and christ church, oxford. he became a barrister, but found a career in journalism and from root to 1904 was editor of the st. jumes’s gazette, afterwards assisting mr. hugh chisholm in the preparation of the r1th edition of the encyclopedia britannica. having made several unsuccessful attempts to enter parliament, he was, in 1911, returned as conservative m.p. for a division of kent. as a politician he was for some years associated with sir edward carson and the more strenuous opponents of home rule. when mr. baldwin formed his first ministry in 1922, mr. m’neill was appointed under-secretary for foreign affairs; he held that office until early in 1924 and returned to it in nov. of the same year again under mr. baldwin. in 1925 he was made financial secre- tary to the treasury. macveagh, wayne (1833-10917), american lawyer and diplomatist (see 17.269), died in washington, d.c., jan 11 1917. madagascar (see 17.270) has an area of about 228,000 sq. m., and a population (r91r) of 3,153,511; (1921) of 3,272,301. in 31921 europeans—nine-tenths french—numbered 19,359, asiatics 8,135. tananarivo (antananarivo), the capital, had 58,459 inhabitants. the comoro islands (see 6.794) were annexed to madagascar in 1914. they had (1921) 109,860 inhabitants. history.—yrench policy in madagascar since the appoint- ment of m. picquie as governor-general in 1g10 has been directed not only to material development and to attracting french settlers to the island but also to the training of the natives to ways and outlook essentially french. the former dominant race, the hova, who had adopted protestant forms of christianity and had the largest number of educated persons, was deprived of all trace of political ascendancy, and special at- tention was paid to the sakavala, the betsimasakara and other tribes. nowhere, however, was a purely native rule under tribal chieftains allowed. at the same time, large numbers of natives were employed in the french administration and the few malagasy who became thoroughly assimilated were given french citizenship (there were about 150 native french citizensin 1924). notwithstanding these measures, the growth of a sense of malagasy nationality could be discerned. among the educated 761 natives dislike of french rule continued strong for many years after the conquest of the island in 1896. their discontent culminated during the world war in the formation of an anti- french secret society, whose members included a large pro- portion of the native officials. the existence of the society which, it was alleged, plotted the simultaneous ‘ removal ”’ of the europeans by means of poison was discovered early in 1916. the society was rigorously suppressed and hundreds of malagasy were condemned to hard labour in the comoro islands. the death of ranavalona iii., the last queen of madagascar, in exile in 1917, was a blow to hova aspirations. gradually, conditions in the island improved. gradually, too, a better class of european official was sent out. the number of french functionaries was, however, large and was a drain on the scanty colonial revenue. malagasy troops were employed in considerable numbers in trance during the world war and subsequently in morocco and in syria. they formed, however, inferior fighting material and the influence of the returned soldiers on their countrymen was not good. other disturbing factors were the spread of alcoholism and of malaria and pulmonary disease among the people, leading to a marked decrease in the number of hova and other races. a brighter prospect was, however, shown in the marked at- tention paid by the french to education, and largely by this means the party among the natives attached to the french con- nection was built up. primary schools were established in the villages, education was made compulsory between the ages of 8 and rq, and in all schools the children had to learn french. nearly 100,000 children were attending school in 1925. the primary schools were supplemented by excellent regional schools—where lads were trained to become officials—and at ‘tananarivo and other towns there were means for higher education, including medical and agricultural schools. another method by which the class of natives supporting the administra- tion was increased was the lavish grant of decorations, including the dragon of annam, the star of anjouan and the etoile noire, as well as grades of honneurs (12 classes), and medals such as the merife agricole, the merite indigene and la medaille du travail. m. marcel olivier, who became governor-general in 1924, adopted a policy of decentralisation of the administration— greater local autonomy and the employment of more natives and in more responsible posts. while there was no form of popular government economic and financial delegations existed and the plan of the administration was laid before them. the pro- gramme for 1925 laid special stress on the need to increase means of education, promote public health and to guide the natives, who after 30 years of french rule were taking larger views of life —and incidentally dressing largely in european fashion—upon the right road. relations between the protestant missionaries and the administration, after a period of strain, had reached a generally satisfactory position, and a larger share of the work was undertaken by french evangelical societies. the protestant missions had to meet, however, increasing and sustained efforts by the french roman catholic missions. economic conditions —development of the natural resources of the island, if somewhat slow, was real. the chief products are rice, coffee, manioc, cattle and graphite. cultivation is mainly by malagasy; the number of french settlers on the land 1s small. in 1924 white colonists were cultivating 150,000 hectares; natives 1,110,000 hectares. although as the result of a protective tariff the great bulk of trade is with france, about one-seventh is with great britain and much british capital is invested in the island. a feature of the commerce is that exports exceed imports both in quantity and value. in 1g1o the exports amounted to 80,000,000 tons and imports to 61,000,000 tons; in 1924 ex- ports were 302,000,000 tons and imports 90,000,000. as to value, the difference in the exchange rates of the franc and the increased cost of commodities prevent exact comparisons. the figures show the external trade (imports and exports) at 78,875,000 frs. in 1910 and 646,605,000 irs. in 1924. means of communication were greatly improved by harbour works and the building of roads and railways. by 1925 there were 1,500 m. of first-class roads and 540 m. of railway. the 762 chief railway (240 m. long), connecting the port of tamatave with tananarivo, was opened in 1918. from this railway a branch line goes northward, and from tananarivo a railway (107 m. long) opened in 1923 runs south to antsirabe. there is a road but no railway to majunga, the chief port on the west coast. canals have been made and irrigation works carried out. public buildings are handsome and solid, built with an eye to future developments. revenue is derived mainly from customs and a poll tax; expenditure was largely on the civil service. the budget of 1913, the last normal year before the world war, balanced at 32,000,- ooo frs.; in 1924 the budget was balanced at 100,000,000 frs.; in effect, taxation and receipts had not increased. it was then realised that if economic progress was not to be checked, a revision of taxation was essential. bibliography.—the standard work on the island is the hwistotre physique, naturelle et politique de madagascar (1875, etc.), in many quarto volumes by alfred grandidier (1836-1921) founded on his exploration of madagascar in 1865-70 and subsequent researches. besides this great work, of which the latest volume appeared in 1917, grandidier edited a collection des ouvrages anciens concernant mada- gascayr (1903, etc.), of which vol. 9 was published in 1920; see also james sibree, a naturalist in madagascar (1915) and fifty years in madagascar (1924); g. grandidier, le afyre de vilers, duchesne, gallieni. quarante annees de l'histoire de madagascar, 1880-1920 (1923); jean lefranc, ‘‘ la prosperite et les besoins de madagascar,”’ in renseignements coloniaux (dec. 1925); guide-annuaire de madagascar et dependances. (po rc) madras, india (see 17.291), capital of the madras presi- dency, and the third largest city of india, had a population of 526,911 1n rg2t, very largely hindu. madras is rapidly growing; the suburbs are extending, and many of the gardens in the city itself have been divided to provide further building sites. work was in progress on a drainage system in 1924, and new waterworks have much improved the health of the city. there are large indus- trics (12 mills employing 19,000 hands in 1924). the municipality was reorganised in 1919; there are 50 councillors, 41 elected and five appointed by government, under an annually elected presi- dent. a fine council chamber has been erected behind the goy- ernment secretariat. proposals for the improvement of the port, including a new quay, were made in 1924. the present harbour accommodates 15 vessels drawing up to 30 feet. the harbour works act as a breakwater, and since they were built the foreshore has considerably extended. madras, university of (sce 27.775).—since 1912 a small teaching staff has been attached to the university, and by an act passed in 1923 the reorganisation of the university as a teaching and residential university was authorised. it still exercises control over the quality of the teaching in its constituent and afiiliated colleges. in 1923 it received rs. 45,200 under the will of sir william meyer, g.c.s.i. fifty-three institutions are affihated to it and recognised in degree courses in the faculties of arts and science, education, law, medicine, engincering, agriculture and oriental learning. madrid (see 17.292), with a population of 813,991 in 1923, is the capital of spain and the largest city. old madrid is disap- pearing, and many of the alleys east of the palace have been pulled down, whilst a number of massive and pretentious buildings have recently been erected. a cathedral is being built on the site of an old church in the calle de baileu, and an anglican church was consecrated in 1925. a large bull ring and stadium have been opened and an underground railway, the first in spain, was fin- ished in 1924. owing to violent speeches in criticism of the government made there, the athenaeum club was closed in 1924 and handed over to the production assembly, a newly formed economic body. in 1925 the rockefeller institute gave £85,000 for the establishment of an institute of physics and chem- istry. it was decided in 1925 to remove the hippodrome race- course to allow of extending a housing scheme and the paseo de la castchana. the cost of living in madrid is notably high. maeterlinck, maurice (1862- ), belgian essayist and dramatist (see 17.298), presents a markecl contrast in his later work published during the 2oth century, after he settled in france, to his earlier works, published before he left belgium. madras—magnetism several of his pre-war essays, collected in the buried temple (1902), the double garden (1909), life and flowers (1907), and more particularly his book on death (1912), are inspired by a reaction against his early mystic and fatalistic tendencies. the same contrast applies to the spirit of such plays as monna vanna (1909) and jafary afagdalene (1909), in which the action is con- centrated in a few important scenes, more according to the racinian than to the shakespearian method. the keen interest displayed by maeterlinck in shakespearian drama is nevertheless shown in his essay on king lear, life and flowers, and in the translation of macbeth (1910), written for a special performance given in the abbey of sainte wandrille. the biune bird (1910), produced in 1911, still increased the popu- larity of the belgian writer in english-speaking countries. it was followed by the betrothal (1919), produced in london in 1921. from the technical point of view, these fairy plays mark a return to the poet’s early symbolism. during the war mace- terlinck wrote a war play dealing with the german occupation of belgium: the burgomaster of stilemonde (1920) produced in london by sir j. martin harvey. the miracle of st. anthony and mountain paths appeared in 1919, and two more plays in a modern setting, the cloud that lifted and the power of the dead, in 1923. most of the works of maurice maeterlinck have been translated into english by a. teixeira de mattos. after the latter’s death bernard miall and f. m. atkinson undertook this work. magazines: sce newspapers; periodicals. magic: see anthropology; conjuring. magnesium: see electro-metallurgy. magnetism (see 17.321). this subject may be studied fur- ther in the articles crystallography, spectroscopy and terrestrial magnetism. theories of ferromagnetism.—langevin’s theory of paramag- netism has been extended by weiss! to ferromagnetism by the introduction of a hypothetical molecular field ef, proportional to the intensity of magnetisation i. this hypothetical force is not necessarily magnetic. the relation between i and the ex- ternal field ii; is determined by the equations cosha 1 == -* (x) sinha a | lid t = h=h,+ ha, h,= ni, ihp= nm (2) where m is the moment of a magnetic atom, r the gas constant, ‘t the absolute temperature, \ a constant specific for the sub- stance, n the number of atoms per unit volume and ip the maximum possible intensity of magnetisation when all the mag- netic atoms point in the same direction. these equations require that in the absence of an external ficld (1i,;~=0) in general the intensity of magnetisation i will not be zero, but will have a defi- nite value given by eliminating a between the equations (1) and ; rt | uae cif (3) and solving for i. this gives a single intensity of permancnt mag- netisation which is stable, but disappears, and with it the ferro- magnetism, at a definite temperature, the critical temperature, given by to=amiy/3r. if by means of this equation r/am is eliminated from (3) and the value of a thus obtained substituted in (1) the resulting equation is of the form tlo=i(t/to) (4) where the function f is a purely algebraical function of the varia- ble t/to the same for all substances. thus if the intensity i of permanent magnetisation is expressed as a fraction of the maxi- mum possible intensity of magnetisation ip, and at the same time the absolute temperature t is expressed as a fraction of the critical temperature ty, the theory leads to a characteristic equa- tion for the intensity of permanent magnetisation (analogous to the equation of state for a gas) which is identical for all ferromag- neticsubstances. in the neighbourhood of the critical temperature orgs. (s) 1p. weiss, journal de physique, vol. 6, p. 661 (1907). magnetism where i is the actual intensity of magnetisation in an external field hy, so that if hy, is kept constant the i, t diagram will be a rectangular hyperbola. curie’s measurements with iron afford an approximate confirmation of (5). an alternative theory of ferromagnetism has been put for- ward by k. honda and j. okubo.) this theory is largely a mathe- matical working out of the older ideas of ewing, and is cleveloped by the authors with a special view to the examples of iron, cobalt and nickel, metals which are known to consist of a mass of cubi- cal crystals. in the natural stable configuration the axes of the elementary magnets are aligned parallel to the axes of the cubic crystals. the actual magnetisation is determined by the dis- placements under the influence of the external field and of the fields due to the neighbouring magnets. to account for tempera- ture effects some spinning of the elements has to be invoked. the theory is made to give a good account of hysteresis and a number of other phenomena, but the thermal side of it appears rather forced. honda? states that the investigation of the binary alloys forming a solid solution with each other shows that an alloy of a paramagnetic with a ferromagnetic metal can be obtained which has a susceptibility of any value lying between those of the two metals. hence the two classes cannot be sharply distin- guished by the magnitude of the susceptibility, but each class is an extreme member of a series of which the intermediate mem- bers can merge continuously inte each other. in high fields the disparity between the intensities of magnetisation of manganese and iron is very much less than in fields of the order required to produce saturation in the iron. ewing? has recently changed his model to meet some objec- tions applicable to the older form. _ ferromagnetic crystals --the magnetic properties of crystals are of fundamental importance, because metals such as iron con- sist of a mass of interpenctrating crystals. individual crystals of pyrrhotine,? magnetite’ and iron® have been investigated. pyrrhotine (fe;ss) is a hexagonal crystal. it is very difficult to magnetise along the hexagonal axis. of the two perpendicular axes one is called the axis of easy magnectisation: the properties in the direction of the other are similar to those along the hexag- onal axis, but the difficulty of magnetisation is not so great. the curve of magnetisation (i, h curve) along the easy axis is re- markably simple. if a correction is made for the demagnetising force and some little allowance for the material irregularities which are almost inevitable in most minerals the diagram re- duces to a rectangle. if the specimen is unmagnetised at first it remains unmagnetised till the value h.=15-4 of the coercive ficld is reached, when the intensity of magnetisation suddenly jumps to the saturation value i,=47 gauss, at which it.stays for all values of h between —15.4 and +0. at h= 15-4 the magnetisation suddenly reverses and stays at —47 gauss for values of h between —0o and +15-4. the constancy of the intensity of magnetisation is actually verified by the experi- ments directly without any corrections over a range of h from about 7oo to 11,000. if the direction of h does not lie along one of the axes the direction of i no longer coincides with it. the intensity of permanent magnetisation has been found to agree with the equation of state (4) above for magnetite from — 79°c. to +587°c., at which temperature the ferromagnetism disap- pears (to). other substances show a fair correspondence with this requirement, but the agreement is not precise. the value of the molecular field deduced by webster from measurements with single crystals of iron is not only very small compared with the values obtained for pyrrhotine, but is much less than one- thousandth part of the values which have been got by other methods for iron in bulk. this discrepancy would seem to call for serious investigation. 1k. honda and j. okubo, phys. rev., vol. 10, p. 705 (1917). | 2k. honda in sir r. glazebrook’s dictionary of applied physics, vol. 2, e. 519 (1922). 37. a. ewing, roy. soc. proc., a, vol. 100, p. 449 (1922). 4p. weiss, journal de physique, vol. 4, p. 469, p. 829 (1905). 6p, weiss, journal de physique, vol. 6, p. 667 (1907). 6 webster, roy. soc. proc., a, vol. 107, p. 496 (1925). 763 muagnetisation in iron, steel, etc., a discontinuous process.‘— if the induced currents used to measure the change of induction are highly magnified by amplifiers, and sufficiently rapid de- tectors, such as oscillographs or telephones, employed, the i, h curve is found to consist of a succession of vertical and hori- zontal lines like steps. this is apparently due to the sudden mag- netisation of successive elements of the material. these may be of considerable size, but it is doubtful if they are single crystals. paramagnetism.—curie’s law kt =i,?/3r = c(curie’s const.) (6) where k is the susceptibility, has numerous exceptions. some of these are doubtless due to the universally present diamag- netism, to change of molecular aggregation and the like. in the case of paramagnetic solids the law requires a general amend- ment, kamerlingh onnes and his collaborators having shown that at temperatures down to about 80°k it should be re- placed by k(p+a)=c (7) where a is a specific constant for each substance. equation (7) is sometimes known as weiss’s law. this law breaks down at the © very lowest temperatures, the deviations shown by different sub- stances becoming very complicated and individual in character. gyromagnetic hffecis—in 1907 o. w. richardson * showed that a delicately suspended rod should spin about the axis of magnetisation owing to the turning of the electron orbits during the act of magnetisation, and calculated the magnitude of the effects to be expected. if u. and m, are respectively angular momentum and magnetic moment per unit volume generated for any axis o,, n,n numbers of electrons per unit volume, m,m masses of electrons and a,a the respective mean areal velocities about the axis o (capital letters referring to positive and small letters to negative electrons), then u.s.=2(n m a + nm a) (8) and m.=n e a+nea (9) if the positive parts of the atom are stationary the ratio u2/me reduces to 2m,‘e, andin any event it should be independent of the strength of the field. a search made at the time did not succeed in satisfactorily separating the effect from parasitic disturbances. it was first clearly established experimentally by einstein and de haas !° in 1915, and has since been carefully measured by a num- ber of experimenters" for iron, cobalt, nickel, heusler alloys and magnetite. meanwhile, in1rg14,5. j. barnett ? had established the existence of a converse effect, viz., the development of a mag- netic field along the axis of revolution of a body when made to spin in a field-free space. the intrinsic magnetic field which would give rise to an equivalent magnetisation is calculated as (10) when only negative electron orbits are considered, w being the angular velocity. the experiments show that both u2/m. and ii‘w are very close to m/e and not equal to 2m/e. this implies that the motions of the positively charged parts of the atom must be considered. if twice as many quanta of angular mo- mentum are assigned to the electrons as to the nucleus this so-called gvromagnelic anomaly is accounted for.’ a third gyromagnetic effect, viz.,a magnetic intensity produced by a revolving perpendicular magnetic field, is anticipated, but has not yet been established experimentally.“ h= 3 e 711. backhausen, phys. zeits., vol. 20, p. 401 (1919); b. van der pol, proc. acad. amst., vol. 23, p. 637 (1921), p. 980 (1922); e. p. t. tyndall, phys. rev., vol. 24, p. 439 (1924). §8l.c. jackson, phil. trans. r. s., a., vol. 224, p. 1 (1924). this paper reports important additions to our knowledge of paramagnetic crystals. *o.w. richardson phys. rev., (1), vol. 26, p. 248 (1908). 1 a einstein and w. j. de haas, berichte der deutsch. physik, ges., vol. 17, p. 152 (1915); de haas, zbid., vol. 18, p. 423 (1918). cf, chattock and bates, phil. trans., a, vol. 223, p. 257 (1922); sucksmith, roy. soc. proc., a, vol. 108, p. 638 (1925). 12 phys, rev., (1), vol. 6, p. 239 (1916); proc. amer. acad. arts and sciences, vol. 60, p. 125 (1925). 13 o, w. richardson, roy. soc. proc., a, vol. 102, p. 538 (1922). 4 j, w. fisher, roy. soc. proc., a, vol. 109, p. 7 (1925). 764 the magneton and space quantisation.—as a result of his observations of discontinuous changes in the apparent value of the curie constant for magnetite, and for other reasons, weiss! put forward the view that the magnetism of para- and ferromag- netic substances arose from a definite atom of magnetism. this weiss magneton had a magnetic moment of 1-85 to! gauss xx cm. the experimental evidence for the reality of this fundamen- tal unit is very unconvincing. there is, however, according to the quantum theory (q.v.) a kind of fundamental unit of mag- netic moment: the angular momentum of the electron orbits ts limited to integral multiples of h/27,h being planck's constant, and we have seen above that the magnetic moment of such an orbit is proportional to its angular momentum. the value of this unit of magnetic moment, the “ bohr magneton ”’ is eh/47m = 9:23 x10 7! gauss xx cm. magnetic moment, however, is a vector quantity, so that the effect of compounding a number of such moments is more than a matter of mere addition. thus no mag- netic atom in the simple sense is to be anticipated. there should, however, be a tendency to certain discrete values owing to space quantisation.2 in general if there is an axis of symmetry in the structure of the substance, or if such an axis is supplied by an external field, the quantum conditions require not only that the angular momenta about the polar axes of the orbits, but also their components about the axis of symmetry, should be integral multiples of h/zr. this double limitation restricts the orienta- tion of the orbits to m+ 1 distinct planes where mh/27 is the total angular momentum. the numbers of weiss magnetons per atom have usually been deduced from the curie constant c by the on fo ~ o cos?@ where m is the molar magneton (1123-5 ; n relation c= gauss), r the molar gas constant, and # the angle between the polar axis and the field, the average of cos?@ being taken on the assumption of equal probability for any direction. if, however, the averaging is confined to the discrete values just referred to, the number of weiss magnetons which should correspond to the successive integral values of m from o to 6 are o, 8-6, 14:1, 19°2, 24°4, 29°4, 34:4. there can be little doubt that the more reliable experimental values have a strong tendency to settle down at these numbers, and a plausible account can be given of such deviations as seem well established.* gerlach and stern* have shown that a fine beam of atoms when passed through a very inhomogeneous and powerful magnetic field is split into two in the case of cu, ag, and au, into at least three in the case of ni, and there is no effect in the case of sn, pb,and fe. the split- ting in the case of cu, ag, and au, corresponds (the accuracy for ag is about 10%) to a magnetic moment of 9-23 x10 #4, thus this very important experiment establishes the reality at the same time both of space quantisation and the bohr magneton. some recently discovered changes with pressure in the susceptibility per unit mass of gases at low pressures are no doubt intimately connected with the phenomena discussed in this section.$ magneto optics —-paschen and back® have shown that in strong fields the complex zeeman effects shown by multiple spectral lines in weak fields become simplified, the separations becoming integral multiples of the lorentz-larmor value. the change is a continuous function of the field strength. the mag- netic response of multiplets as shown by their zceman effects is determined by their natural multiplicity, and there seems little doubt that this latter arises from the magnetic fields of the atoms. in an atom whose maximum permanent multiplicity is r and which is in an excited state such that its azimuthal quan- tum number is k, a good case can be made out that the maximum eh ‘ magnetic moment is equal to i aaa the magnetic mo- tl, weiss, le radium, vol. 8, p. 301 (1gtt). 2 cf. a. sommerfeld, atomic structure and spectral lines, eng. trans. of 3rd ed. (1923). 3 cf. e. c. stoner, phil. mag., vol. 49, p. 1289 (1925). 4w. gerlach and o. stern, ann. der physik, vol. 74, p. 673 (1924); vol. 76, p. 163 (1925). e a, glaser, ann. der physik., vol. 75, p. 459 (1925). 6f, paschen and e. back, ann. der physik, vol. 39, p. 897 (1912); vol. 40, p. 960 (1913). magnetism, terrestrial ments so deduced show a reasonable agreement with those got from measurements of the paramagnetic susceptibilities of cor- responding ions. each starts from zero, rises to a maximum, and falls to zero again in traversing the successive elements in the period from k through fe to cu, and there are other resem- blances. one interpretation of the spectroscopic data requires that the magnetic moment of the atomic core should be twice as large as that calculated from the angular momentum, an anomaly like that of the gyromagnetic anomaly already considered and capable of the same explanation.’ permalloy.—h. d. arnold and g. w. elmen® describe a nickel- iron alloy containing 78-5° 4 ni, which has remarkable magnetic properties. the initial permeability is about 13,000, the area of the hysteresis loop is jj; that for soft iron and the maximum permeability 87,000 for b about 3,000. the saturation intensity of magnetisation is comparable with that for iron, and the alloy approaches saturation in the earth’s field. see ‘ magnetic measurements and properties of metals,” in sir r. glazebrook, dictionary of applied physics, vol. 2: electricity (1922); p. l. kapitza, “ production of high magnetic fields,” roy. soc. proc., a, vol. 105 (1924); l. w. mclkechan, “ ferromag- netisn,’’ jour. franklin inst. (may and june i924). (o. w. r.)