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SHELBY M. HARRISON,* New York, N. Y. (written discussion ?).¬Your secretary requested a brief description of the Russell Sage Foundation, in order that members of the Institute, if they should desire to avail themselves of it, would know what type of service is offered to them through our institution. The foundation was established in 1907 by the gift of Mrs. Russell Sage of $10,000,000 as a capital fund, the income of which is to be spent for the improvement of social and living conditions in the United States. One of the lines of activity which the foundation has felt would lead toward this end is the development and promotion of community surveys; and because the scope and methods followed in these surveys are very similar to the scope and method of much of the institution's work in general, an idea of its main activities can perhaps be given best by describing one of our surveys. Incidentally, it may be pointed out that antecedent to the survey stand at least two important facts: first, the recognition. that communities are active, not static forces, that they develop, that changes in. material and human relationships occur continuously, and that with them come new social and civic problems which must, in many cases, be diagnosed and prescribed for anew; and second, the reality of scientific advances along lines which make possible at least some measure of solution of the problems. Evidences of these changes are abundant; many of them are found in the rapid growth of cities in the last few decades. Villages in agricultural districts, places where everybody knew everybody else, where the pulpit had been long the chief or only influence molding public opinion, where the air was unclouded by the smoke from factory stacks, where the water supply was not affected by pollution, where sunlight and building

Jan 5, 1918

By J. S. Ll. Leach, M. B. Bever

THE system copper-nickel exhibits complete solid and liquid miscibility1 The thermodynamic properties of such a system would not be expected to deviate greatly from ideality. Although the evidence is conflicting, anomalies in the composition dependence of various physical properties of solid copper-nickel alloys suggest that mixing may not be ideal.' From measurements of the Hall coefficient it has been concluded that clustering occurs in these alloys. ' Considerations involving the phase diagram of the ternary system copper-nickel-chromium have led Mei-jering3 to predict a positive heat of formation for solid copper-nickel alloys. An electrochemical investigation of the activity of nickel in copper-nickel alloys showed unexpectedly large positive deviations from ideality.4 wagner5 has proposed that if the entropy can be considered ideal, these measurements would yield the following equation for the heat of mixing at 700°C H" = 3380 x,vl (l-xVi) cal per g atom [I1 The heat of formation at 722°C of solid copper-nickel alloys of the equiatomic composition has been measured in a reaction calorimeter as 540 cal per g atom. This note reports calorimetric measurements of the heat effects on dissolution of some copper-nickel ndon: in tin. These measurements were preliminary to a larger investigation, which was later discontinued. From them the heats of formation of the alloys can be calculated, if certain assumptions are

Jan 1, 1960

By Walter Henoch

THE subject of my talk is, "What 'the college, student expects when he gets out of college." Since all of us, here tonight are engineers, I think it will be proper to limit the discussion to "What the engineering student expects when he emerges from college." It might be well to con-sider just why we chose engineering rather than some other of the many courses open to us. We certainly did not choose it because it is easy nor because we thought it would be a very pleasurable way to spend four years of our lives. The majority of students who choose this profession have a pretty well-formed idea of what an engineering course requires. They at least know that they must work to re-ceive their credits. The minority, which is no small num-ber, are soon disillusioned and as a result they either quit college entirely or they join the' Commerce School. I asked a number of my fellow students just what it was that induced them to join the engineering profession, but it was hard to obtain a clear cut statement from any of them. Some said it was due to environment; others said, they took it because they liked it, and still others said they took it because their folks wanted them to. These state-ments are rather vague and incomplete, but underlying them all is something that the fellows found hard to ex-press. I think it is this: To the layman there is something of romance and adventure about the engineering profes-sion, and this fact coupled with the reputed high salaries and high commands of certain noted engineers no doubt fired our imaginations and consequently led us to join the ranks of the engineers. No doubt many engineers have gone out into the world and have found little romance or adventure .attached to their work, but nevertheless it is an occupation of a wide diversity of interest, of constant change of scene, and of vivid and human relations.

Jan 5, 1928

By S. G. Bankoff

Ince1 proposed that electrostatic attraction between oppositely charged particles was responsible for slime-coating. Del Giudice2 postulated the metathetic formation of a cementing compound. Wark3 suggested that prevention of slime-coating was related to peptization of the slime. In the experiments of Table I the technique employed was essentially that of del Giudice, with the difference that the particle was examined under a film of water rather than dry.4 In general, the polished particle was agitated for 2 min. in a pulp consisting of 12.5 grams of the slime (—200 mesh) and 50 C.C. of distilled water, washed in three baths of distilled water, and examined at 220 diameters with the Leitz Ultropak. Observations of Brownian movement were made at 850 diameters with dark-field illumination. Several of these experiments do not jibe with the metathesis theory. According to published solubilities,5,6 the lead salts of the anions in experiments c through g are more insoluble than lead carbonate, there- fore should prevent the formation of lead carbonate on the galena surface. In experiment i the calcium oxalate, which precumably was on the calcite surfaces, should have permitted the formation of a lead carbonate cement by virtue of its greater solubility. Experiments j through m show that the addition of lime accelerates the deposition of quartz onto a galena surface. The writer is unable to postulate a satisfactory cementing compound, according to the metathesis theory, to explain this effect. These experiments led to the conclusion that the metathetic formation of a cement-

Jan 1, 1943

By William G. Gates

INTRODUCTION The Heath Steele mine is located in the Bathurst-Newcastle area of northern New Brunswick. It is jointly owned by American Metal Climax, Inc. and the International Nickel Company of Canada who hold a 75% and 25% interest, respectively. The ore deposits of lead, zinc and copper sulphide occur in very fine grained pyrite and/or pyrrhotite masses. A consistent spatial relationship with a quartz feldspar porphyry is characteristic of these deposits and the many other similar sulphide deposits in the district. The two principal mineral assemblages of pyrite-sphalerite-galena, and pyrrhotite-chalcopyrite-pyrite, occupy characteristic positions relative to the enclosing rocks. This feature and the nature of the sulphide mineralization are described and the variations in metal content are noted .with special emphasis on the lead-zinc ore zones. The mine product ion rate is 3,000 tons per day of a mixed lead- zinc and copper ore which is extracted from the B-1 zone. The complex nature of the ores presents many metallurgical problems. Optimum metal recoveries are achieved when milll feed grades are relatively consistent and proportions of the contained metals are with in acceptable limits. Ore outlines and stoping blocks are delimited by close spaced diamond drilling. From this information it is possible to forecast the grade of any portion of a stoping block. Production from the various stopes may then be scheduled so as to achieve an acceptable mill feed grade.

Jan 1, 1970

By W. W. Odell

ONCE it was believed that anthracite or coke were the only fuels generally available and suitable for the generation of water gas, particularly so when this gas was made in the generators of standard carburetted water-gas sets such as are commonly used in the manufacture of city gas. During the past 8 years, practice has changed considerably and it is -now common to find gas plants operating without anthracite or coke and using bituminous coal in the generator. This change in fuel has appreciably increased the marketability and sales of certain coal producers' products; accordingly it is of interest to coal operators and others to know the reason for this change, the present trend in practice and the adaptability of various coals for generation of water gas. This paper briefly discusses these conditions and some of the factors relating thereto. BITUMINOUS COAL NOT IDEAL BUT CHEAPER THAN COKE In spite of many changes which have been made in both process and generating apparatus for using bituminous coal as generator fuel more efficiently, in general it is not an ideal fuel for this purpose. It is supplanting coke because it costs less; it is so much cheaper per ton delivered at the gas works that water gas made therefrom costs less per unit-volume than that made from coke, even though the quantity of generator fuel consumed per therm (100,000 B. t. u.) of gas made is greater with coal. This is the reason why so many city gas plants, as well as others, are using bituminous coal instead of coke.

Jan 1, 1927

By Kenneth Cottingham

The number of completions in 1944 in Ohio was only slightly greater than completions in the preceding year, but the initial daily volumes both of oil wells and gas wells declined considerably. The dry-hole ratio was a little lower than in 1943, even though in the year under review considerable effort was made to find new production. No new areas of consequence were discovered. Thirteen new gas pools, the largest of which was 1000 acres and the average 565 acres, were opened during the year. Eleven of these pools were in the Clinton sand, one was in the Oriskany, and one was in the Berea. Approximately 15 small pools might also be rated as discoveries, but because only one or two wells have thus far been completed in each, they cannot at present be properly evaluated. The latter pools average about 120 acres each. Some extensions were made to existing gas pools. The number of oil wells drilled was only one less than in 1943, yet compared with the year 1941, when twice as many oil wells were drilled, the difference is startling. Effective Aug. I, 1944, a blanket subsidy was granted of 35¢ per barrel on all Cleveland-Chatham, Coming, and Lima grades of oil, and 75¢ per barrel on Pennsylvania grade crude. The subsidy was authorized by the Office of Price Administration, with reimbursement to purchasers of the various grades made through the Defense Supplies Corporation, a branch of Reconstruction Finance Corporation. For several years the small operator, particularly the owner of stripper wells, was in a serious position. The subsidy has been a means of real help and, in addition to aiding the operator, it has prolonged the life of many small wells that otherwise would have been abandoned, with consequent loss of daily production and unre-covered reserves. It is questionable whether the price increase is sufficient to revive production of Corning grade, which has

Jan 1, 1945

By Z. F. Danes

Combination of gravity data and density logs makes it possible to determine the structural relief. Under a wide class of geologic conditions, the solution is unique, or limited to a single parametric system of solutions. As a useful byproduct, the method yields a new way to construct derivative maps, continue the field up or down, subtract regional anomalies, and perform smoothing. In the past, the problem of interpreting gravity anomalies in terms of structural geology was solved along two main lines: 1) A body of a certain shape and density contrast was assumed and the corresponding gravity anomaly calculated, analytically for simple bodies, graphically and/or numerically for more complex ones; then the computed anomaly was compared with the observed one, and the assumed shape corrected according to the differences between the two. 2) The anomaly is assumed to come from a warped interface between two media of different density; the relief of the warping is assumed small compared to the depth of burial, so that the structure can be approximated by a flat horizontal surface of variable density distribution. The first method is a standard technique, described in every text book on applied geophysics, and is well applicable, for bodies with predominant vertical dimension. The second one, probably first used by Tsuboi and Fuchida,' is mathematically more elegant. It applies to the fashionable field of integral transforms (Bullard and Cooper, 2 Tomoda and Aki, 3 Dean 4) and is useful mainly in cases when the vertical relief of the structures is comparatively small. 30th methods, tacitly or openly, assume a density discontinuity across the boundary of the two media, while within each medium the density is constant. However, the recent invention of the gamma-gamma

Jan 1, 1962

Through the generosity of Sir Robert Hadfield, Honorary Member, the Directors of the American Institute of Mining Engineers are enabled to announce the Hadfield Research Prize of $1,000 for the best contribution to the publications of the Institute upon the general subject of The Different Forms and Combinations of Carbon with Iron, including those in Iron Alloys. The prize will be awarded at the Annual Meeting of the Institute in February, 1916, to the best paper upon this subject which is presented to the Institute before Nov. 1, 1915, provided such paper is deemed worthy by the Institute's Iron and Steel Committee. The following suggestions are also added for the guidance of those who may take part in this research. While' it is not desired to define closely the exact lines or scope of the proposed research, as it is advisable to make these as broad as possible, the object in mind maybe said to be generally as follows: To elaborate and find out the best methods of determining the forms of carbon in steel or iron, including those in iron alloys. A portion of the work would probably be a continuation of the researches which have in the past been carried out by Jullien, Abel, Muller, Ledebur, T. Sterry Hunt, Akerman, Arnold, Stead, E. D. Campbell, Hogg, Parry, Upton, and others. In a generic way, metallurgists now speak of carbides, sub-carbides, double carbides, special carbides, and other combinations. It is very desirable that these should be accurately defined and understood. It is also desirable to know whether there are other or new forms; if so, can these be separated and their characteristics obtained. It may be interesting to point out that the carbon compounds now definitely known are stated to number over 80,000. It is very probable, therefore, that there is room for much valuable and useful research to be carried out with the object of increasing our knowledge of the various combinations of carbon with iron, as probably some of these are still unknown

Jan 5, 1914

By C. M. Weld

Attention has been turned recently to the exploration and development of certain large blanket-deposits of brown iron-ore in Cuba. The most conspicuous of these to-day, and the one upon which the most light has been shed, is the Mayari deposit, situated about 15 miles south of Nipe bag. Here the Spanish-Aniericau Co. has sole control over 18,500 acres of ore-bearing lands, reported by its engineers to contain 500,000,000 tons of ore. The necessary plant and equipment, with docks and railways, is now under construction for the early marketing of this ore. A similar deposit, and undoubtedly the next to be exploited, is the ore-field at Moa bay, where from 13,000 to 15,000 acres of ore-lands, immediately adjacent to the shores of an excellent harbor, have been generously covered by numerous mining-claims, practically all controlled by four large interests;. This deposit is now estimated to contain approximately 350,000,000 tons, on the basis of dried ore ready for shipment, a figure which may be increased when the western limits of the ore-deposit have been more accurately defined. Other deposits of the same type, but smaller and less accessible, are those at Cubitas, situated from 12 to 15 miles north of Camaguey city,

Jan 1, 1910

By R. Laird Auchmuty

FOREWORD THE A. I. M. E. Subcommittee on Bituminous Mining has been trying for several years to secure the information that was collected by the Marquette Cement Manufacturing Co. on the subsidence of its property caused by mining coal beneath it. The Marquette company was willing to have these data used, but it was impossible to obtain them because the records had been filed away. About two years ago these records became available and the engineering data presented herewith were compiled from them by R. L. Auchmuty, assisted by L. E. Young, who was connected with the collection of the information. On account of the cost, it is impossible to reproduce all of the data here, although the original information is on file with the records of the Committee on Ground Movement and Subsidence. The accompanying charts show representative and average data and give only the engineering information with enough description to tell how it was obtained. It is hoped that all of those connected with the original case will participate in the discussion that this will bring forth. HOWARD N. EAVENSON, Chairman, Subcommittee on Bituminous Coal Mining.

Jan 1, 1931

By F. T. Lee

Directional dependence of strength and deformation properties of the Mount Waldo granite pluton in southeastern Maine is controlled by joints and microfractures whose orientations are linked to flow- induced alignment of microcline crystals. Longitudinal and cross joints which formed during cooling of the mass, as well as much younger sheeting fractures, are commonly associated with subparallel, discontinuous microfractures. The orthogonality of microfractures (open, closed; filled, unfilled; bubble planes) establishes the ease of splitting of the granite. The easiest splitting direction (rift) is subhorizontal, the second easiest direction (grain) is parallel to the cross joints, while the direction of least easy splitting (hardway) is parallel to the longitudinal joints. Static and dynamic measurements made in the field and laboratory established that structural features are responsible for the marked stiffness anisotropy of the granite. In the central part of the pluton the static Young's modulus in the north-south direction averages 31.1 GPa, and 20.9 GPa in the east-west direction; the stiffer direction being parallel to the long C-axes of microcline phenocrysts and microfractures as identified in outcrop, core samples, and thin sections. Vertical downhole sonic measurements of dynamic moduli ranging from 2.5 to 16.2 GPa appeared to be anomalously low when compared to the static horizontal values. However, the field sonic values were confirmed by laboratory sonic pulse testing of oriented cores. The field results reflected closely spaced layers of open horizontal microfractures. Those deformation and strength properties that are closely tied to bubble planes, filled microfractures, and microcline orientation could be extrapolated to greater depths with good hope of success.

Jan 1, 1984

Greater automation of facilities is probably the best hope of the mining industry in its efforts to surmount continually rising labor costs. Underground mining, with its inherently low unit labor output, is especially vulnerable to rising costs, and here maximum automation is becoming increasingly important. One area of such operations that has been receiving a great deal of investigation is that of ore haulage and hoisting, two steps that often account for 10-35% of underground operating costs. Innovations and experimentation by mining firms and manufacturers over the past few years have resulted in larger, faster and more efficient tramming and hoisting equipment, but the White Pine Copper Co., at its operation in the Upper Peninsula of Michigan, is preparing to start up an entirely new concept in haulage later this summer. Known as the Dashaveyor System, it consists of individually powered modules (cars) that run on tracks inside a rectangular tube or on an open trackway at predetermined speeds up to 50 mph. At White Pine the Dashaveyor will be used to carry ore (crushed underground to -10 in.) from the mine to the concentrator. Dr. James Boyd, president of Copper Range Co., which is a 25% shareholder in The Dashaveyor Co., has indicated that if the Dashaveyor meets the expectations for surface operation, it will also be used underground for ore transport in place of the several miles of conveyor belts currently in use (Business Week, July 29, 1967).

Jan 7, 1968

By Robert H. Richards

The group of four papers on ore dreseing read at the Butte meeting, all of them dealing with the recent developments at the Great Falls and Washoe plants of the Anaconda Company, form an extremely important contribution to the subject of ore dressing. It proves the efficacy of the new hindered-settling principles first brought out in a paper entitled Close Sizing Before digging' and later elaborated in a paper entitled Development of Hindered-Settling Apparatus: and it is the first large demonstration on this class of mill that has been made. It must be very gratifying to all mill men to have these papers at hand, charged with careful investigations and results pointing to the conclusions reached; the papers cannot fail to be a great help to every designer of mills and to mill men who are working on this class of concentration. The papers have dealt with their subjects so completely and have demonstrated every point from beginning to end in each case so thoroughly it leaves little for the commentator to say in the way of criticism. Therefore it seems best to him to confine himself to adding a few points of history which he believes will be interesting to the readers. Referring to the paper by Mr. Wiggin, and to the fact that the Richards hindered-settling pulsator classifier was turned down, the writer wishes to say that this classifier was the first of its kind that had ever been introduced, and since that time it has undergone great developments which he believes would overcome the difficulties encountered in the test,. In fact, there was one test made at Great Falls which with the Wilfley tables and vanners brought all the tailings down to 0.36 per cent. copper except the fine slime. Since that time, and since the classifier has been further developed, in one Colorado mill it proved a wonderful amalgam catcher, catching in all

Jan 1, 1914

By George Ross Green

[In discussion of the paper of Mr. J. C. Bayles, read at the New York meeting of September, 1890, Trans., xix., p. 18.1 It is often so difficult to locate the causes of failures of machinery and apparatus which can be examined and studied at leisure, that it is not surprising that the causes of explosions should escape detection. Usually the explosion is the first evidence that anything is amiss, and the time for observing the conditions is necessarily brief. An incident in a welding-works near Essen, Germany, might be cited as exemplifying what trifling causes may lead to disaster, and how difficult, under the most favorable conditions, it may be to discover them. A blowing-engine was arranged with two suction-pipes at each end of the blowing-cylinder—one leading to the air, and the other to the gas-holder. Each pipe was provided with a valve, and all were so adjusted that the cylinder drew in gas and air in the proportions found most advantageous. The gases from the cylinder were carried directly to the furnace through suitable pipes, and while the cylinder was provided with relief-valves, every effort was made to prevent explosions, principally by compressing the gases to a point where the rate of efflux of the mixture was greater than the velocity of combustion, if the expression is here allowable. It was found that the apparatus would work satisfactorily for some time, and then the relative proportions of the mixture would change, and an explosion might have been the result. Experiments consuming days were made to discover a method of averting this danger, but they were unsuccessful, until it was observed that the change in the composition of the mixture of gas and air took place when the gasometer began to rise or fall—the back-pressure due to friction when the holder was rising or its absence when falling being sufficient to change the conditions. As soon as this was discovered,

Jan 1, 1892

By W. N. Logan, P. Simpson

There was less activity in the petroleum industry in Indiana in 1933 than in previous years, owing largely to adverse market conditions. The only development of any consequence was for oil in Perry and Vander-burgh counties in southwestern Indiana, a few gas wells being brought in in Jay County in northeastern Indiana. Indications are that there will be more activity in southwestern Indiana in 1934. Little change may be expected in northeastern Indiana. One hundred and sixty wells were drilled in Indiana in 1933, of which 57 were dry, 44 produced oil, 38 produced gas and 21 either were not completed or information on them was lacking. There were 153 wells abandoned and plugged in 1933, as compared to 205 in 1932. Southwestern Indiana This area centers about Gibson County and is the principal source of oil and gas production in the state. Production is from the Lower Pennsylvanian and Upper Mississippian formations. Oil production for 1932 was approximately 847,000 bbl. and for 1933 was 804,000 bbl. Gas production for 1933 was 942,000,000 cubic feet. The Siosi field, in southwestern Vigo County and northwestern Sullivan County, discovered six years ago, produced approximately 244,000 bbl. in 1932 and 223,000 bbl. in 1933. Production is from Devonian and Silurian formations. The oil is high gravity, but contains considerable sulfur. The Shelburn and other small pools in central Sullivan County produced approximately 68,000 bbl. in 1932 and 2,000 bbl. less in 1933. Production is from one or more of five horizons in the Pottsville and is obtained at 600 to 800 ft. This area also produces approximately 19,000,000 cu. ft. of gas a year, supplying the city of Sullivan. The field is over 20 years old. The Gibson-Pike County area, made up of many small pools, including several in southern Knox and southwestern Daviess counties, produced approximately 486,000 bbl. in 1932 and 450,000 bbl. in 1933. This production is from the Mansfield sandstone of Pennsylvanian and/or

Jan 1, 1934

A. M. CANDY,* Pittsburgh, Pa.-I think more stress should be laid upon the question of welding with the carbon electrode, which we ordinarily call graphite arc welding. Mr. Miller's photograph indicated that the original parent metal had been decarburized to a marked degree. It would be interesting to know the carbon content of the parent metal, and whether or not Mr. Miller has made any investigations to determine if the metal is always decarburized or whether in some instances we actually have carbon injected into the weld, which has been the understanding that has been quite prevalent. There were one or two other points that Mr. Miller brought out concerning which I desire to ask one or two questions: The illustrations that he presented were obtained with what, I suppose, would be termed a real low-carbon steel welding wire, which gives in the deposited metal grains that are more or less symmetrical, whereas the Roebling electrode, which is a mild steel of higher carbon content, apparently gives a columnar structure. I do not know which-of these I structures is more desirable, but assuming that the structure produced by the really low-carbon steel wire is the more desirable, would it not be true that the very low carbon content would, probably owing to high temperatures that prevail in the arc, result in a greater amount of oxidation and probably result in either carrying into the weld more oxide or producing more oxide on the surface as the operator progresses? The short arc is an advantage in all cases. Whether Mr. Miller's trouble is oxide or nitride, the short arc helps him out, because the closer the end of the electrode is to the work the less chance there is for either oxygen or nitrogen to get in. And whichever is the cause of the trouble, the short arc keeps it out by lessening the time in which the steel is molten and the amount of air that gets in. It also makes sure that the molten metal will not fall into the crater. Everything is in favor of the short arc.

Jan 4, 1919

This brief resume of events, transpiring in Mexico, culled from the daily New York newspapers, since the last Bulletin went to press, does not indicate any degree of improvements in the situation. GENERAL ALVAREZ COURTMARTIALED AND SHOT General Francisco Alvarez of the anti-Government forces was captured in the battle in which General Aureliano Blanquet, Minister of War in the Huerta Cabinet, was killed, and was sentenced by a courtmartial and shot in spite of a specific order of the Supreme Court in Mexico City that the execution should not take place. General Alvarez was a member of the staff of Felix Diaz, and was a veteran of the old regular army of Mexico. MEXICO WILL NOT RECOGNIZE MONROE DOCTRINE Failure of the Allied Powers to invite Mexico to participate in the conference of neutrals at Paris aroused President Carranza to bitter resentment, which was enhanced by the incorporation of recognition of the Monroe Doctrine in the covenant of the League of Nations without consultation with Mexico. Statements were issued by the Mexican Foreign Office disavowing adherence to the Monroe Doctrine and announcing the withdrawal of the Mexican representative in France. Carranza had been awaiting an opportunity to get his agent away from Paris for the real reason that he had been unable to secure recognition from either the French or the British Government. Mexico announces, says the New York Times editorially, that "she has not recognized and will not recognize the Monroe Doctrine." "Nobody has asked her to recognize the Monroe Doctrine," continues the editorial. "The enforcement of the principles enunciated by President Monroe does not depend upon Mexico, upon anybody's recognition or non-recognition. The countries concerned in the Monroe Doctrine are the United States on the one hand, and countries not of this hemisphere on the other."

Jan 6, 1919

By Charles B. Dudley

It is evident that, as the size and weight of cars have increased, the demands on the cast-iron car-wheel have become more and more severe. Fortunately, the factor of safety in the cast-iron wheel, as originally made, was so large that it was only when freight-cars approached the capacity of from 80,000 to 100,000 lb. that the question of wheels began to give some anxiety. A moment's thought will show that, as freight- and passenger-cars have increased in weight and size, a much greater duty is required of the same eight wheels than was formerly the case. In other words, although the cars have increased in capacity from 15 tons to 50 tons each, the number of wheels under a car has not been generally increased. It is true, some cars have been equipped with 12 wheels, but this construction is not the rule. Hence the duty which the wheel must perform has become much more severe, and although it was clearly able to stand some increase, there must evidently be a limit somewhere which cannot be exceeded. Meanwhile, it is the part of wisdom to make better wheels if possible, and accordingly, no little study is now being devoted to the requirements for cast-iron car-wheels; and modifications are being made, both by increasing the weight of the wheel and by improving the quality of the metal of which it is made. The desire to improve the quality of the wheel has led to the preparation of specifications for its manufacture; and within the last 15 years a more rigid scrutiny of the wheel is char-

Jan 1, 1905

This brief resume of the events transpiring in Mexico, culled from the daily New York newspapers since the last Bulletin went to press, does not show any degree of improvement in the situation. U. S. WITHDRAWS ARMY FROM MEXICO The American invasion of Mexico lasted less than 24 hours. The troops which crossed the Rio Grande June 15 to put a stop to the firing that was causing death and injury in El Paso were back in their billets on the American side of the border the next night. They had broken up the battle between Villa rebels and the Carranza garrison and driven the rebel forces headlong out of Juarez and into the hills. The Carranza Consul, Garcia, and Gen. Francisco Gonzales are reported by American officials to be pessimistic, if not indignant, at the swift reprisals made by the Americans against the stray shots which were falling in El Paso during the Villa attack on Juarez. In announcing his action in ordering Americans into Mexico Brigadier General Erwin in a formal statement said he had done-so to prevent the indiscriminate firing into El Paso by rebel soldiers, endangering the lives of Americans. "But on no account were they to undertake an invasion into Mexico," continued the statement. Americans with interests in the vicinity of Chihuahua are alarmed lest Villa, smarting under the defeat administered his troops by the American forces, should make a campaign of destruction. General Candido Aguilar, President Carranza's confidential ambassador to the United States, issued to the press, on June 17, a formal statement that "the government and people of Mexico consider as a violation of Mexican sovereignty the crossing of United States soldiers into Mexican territory" and expressing the hope ?that the situation created by the latest occurrences in Juarez will be satisfactorily adjusted between the two countries." Discussion of Mexican affairs was evoked in both houses of Congress by the crossing of the Rio Grande by American troops.

Jan 8, 1919