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By Edgar Marburg, William R. Webster

The desirability of bringing about greater uniformity in specifications governing iron and steel is generally recognized, and has found expression within recent years, in the efforts of numerous technical societies in that direction. When the International Association for Testing Materials was organized at Zurich in 1895, a committee was appointed, charged as follows: " On the basis of existing specifications, to seek methods and means for the introduction of international specifications for testing and inspecting iron and steel of all kinds." The American representation on this international committee consisted originally of five, and now of eight members. In view of the magnitude and importance of the subject, the Executive Committee of the American Section of the International Association for Testing Materials, since incorporated as the American Society for Testing Materials, appointed a committee of 34 members, including the American members of the above-named international committee, to frame standard American specifications for iron and steel. This committee reported on specifications for (1) Structural Steel for ridges and Ships; (2) Structural Steel for Buildings; (3) Open-Hearth Boiler-Plate and Rivet-Steel; (4) Steel Rails; (5) Steel Splice-Bars; (6) Steel Axles; (7) Steel Tires; (8) Steel Forgings; (9) Steel Castings ; (10) Wrought-Iron. These specifications were designed to be fairly representa-tive of the best current American practice, and were adopted by letter-ballot of the Society in August, 1901. The leading engineering societies have participated at various times in the discussion of these specifications and have lent valuable assistance through the appointment of special committees on like, or closely related, subjects. The American Society of Civil Engineers discussed the spec-

Jan 1, 1905

By David Baker

When the skip-hoist was first tried as a means of filling the blast-furnace it made a great many enemies and very few friends among furnace managers. This state of affairs continued until the Duquesne furnaces were built, which demonstrated not only the possibilities of a furnace-stack in the way of production, but also the ability of the skip-hoist to charge the materials necessary to produce the large tonnlage obtained. Every furnace manager, who has operated stacks fitted with the vertical hoist and the hand-barrow system of filling, remembers that the momentous question about the furnace, particularly during a good run, was: "Are you keeping her full ?" and many a good run has been spoiled by the furnace " getting away from the men." With the new birth of the skip-hoist this trouble was eliminated ; but alas! Other and more important difficulties arose. The distribution of the stock, the importance of which is never learned until many different ores and fuels have been tried, demanded closer attention. With all the defects of the hand-barrow system, the distribution—When the top fillers were conscientious in carrying out the scheme of filling arranged after thoughtful consideration by the manager—mas above criticism. It is said that the modern skip-hoist, equipped with an elliptical hopper and receiving-cylinder, and discharging over a small bell into the main hopper, will give just as good results as those obtained with hand-barrow charging, but I cannot agree with this statement. I grant, that under very favorable conditions, the mechanical furnace-top will do apparently as well as the

Jan 1, 1905

By M. G. Magnuson, H. O. Hofman

When dry chlorine gas is made to act in the cold upon fiuely-divided gold,' it converts the latter with evolution of heat into auro-auric chloride, Au4 Cl4, a hard, dark-red, hygroscopic salt. Moisture splits this salt into aurous and auric chloride, Au²C14 = AuCl + AuCl³; treatment with water converts it into auric chloride and gold, 3 Au²CI4 = 4 AuC1³ + Au². Aurous chloride, when stirred with water, undergoes a similar decomposition, 3 AuCl = AuCI, + Au,. These decompositions of auro-auric chloride and of aurons chloride furnish the explanation for the practice of moistening an ore before it is treated by the Plattner chlorination-process; practical experience having shown that gaseous chlorine gave an unsatisfactory extraction with dry ore. According to Rose12 fine gold is acted upon more slowly by chlorine than gold containing some base metal, e.g., copper. He also says that small quantities of silver increase the rate of solution, but adds that the coating of silver chloride formed, checks, and finally stops, further action, if the percentage of Silver be increased beyond a certain undetermined amount. Bromine3 acts upon finely-divided gold in a manuer similar to chlorine; the auro-auric bromide, Au²,Br4,, however, is not hygroscopic. Upon treatment with water it is decomposed as is the corresponding chlorine salt. It is generally believed that bromine does not act as energetically upon gold as does chlorine. This seems to be borne out by the results in the leach- +1MASSACHUSETTS INSTITUTE OF TECHNOLOGY, BOSTON, MASS.

Jan 1, 1905

By H. D. Hoskold

This instrument, shown in Fig. 1, is not generally known, though it has been used in England, and found very practical, handy and useful in work not requiring a transit or theodolite. It is not only a good miner's dial, but a circumferentor as well; that is, it can measure horizontal angles like a theodolite. The magnetic bearings are conveniently read on the inward-beveled upper divided circle; while another circle, graduated on the base-plate, is used for reading the horizontal angles with a vernier. Two leveling spirit-bubbles are sunk in the same base-plate. The vertical divided semicircle is attached to the compact-box by two short axes, which permit the semicircle, with its plain sights, to be turned down to a horizontal position, and rest upon a pin, which relieves the axes from strain. This adjustment gives a clear view of the needle and vernier, and protects the instrument from injury, when carried through low mine-workings. A groove in the semicircle receives a sliding-bridge which carries the plain sights, and a vernier for reading vertical angles. A ball-and-socket-headed tripod is used; but sometimes the instrument is mounted on parallel-plates and level-ing-screws; and sometimes a telescope is attached, instead of the plain sights. The instrument is admirable for all such Mexican surveys as Mr. E. A. H. Tays describes ;l and saves so much time and labor as to be vastly superior to the less accurate hanging-compass called by him a " bully " instrument. If the hanging-compass was ever used in England, it has long since given way to more modern and superior instruments.

Jan 1, 1905

By Sydney H. Loram

TEIS paper, which is merely an arrangement of data collected during several hurried journeys, is offered to serve as a record, until such time as a better substitute be compiled. My observations were confined, as far as possible, over the entire distance, to the actual river valley; because near the Central Cordillera the country is so mountainous as to be im; passable in any direction but that of the dominant valleys. The river is not navigable anywhere, and for the first part of its course is a mountain torrent that runs down the bottom of narrow, almost vertical-sided valleys, through which the only road requires repeated fording, and often following up the bed of the stream ; but the rock-walls, standing clean and free from debris on either side, present the different formations with remarkable distinctness. A topographical map and a cross-seetion of the Rio Huasco is given in Fig. 1. The Rio Huasco practically rises from Laguna Grande, a lake about 17 km. from the Argentine boundary, and 3,135 m. above se-level, which is fed by direct snow-water, and by a few streams varying from a considerable volume, when supplied by the melting snow, in late spring, to little or nothing during the rest of the year. It is a somewhat pear-shaped body of water, about 1.5 miles in length and half a mile in average width, with a reported maximum depth of 45 meters. It was formed by the choking up of a narrow continuation of the same valley with blocks of an agglomerate mentioned later. The present level is some 5 m. below high-water mark (to which point, according to local accounts, it has not been filled for 35 years). In the intervening margin is a calcareous deposit about 4 m. thick, formed by the rapid evaporation of the water in the exceedingly dry air, and aided by the capillary action of an aquatic plant, growing in thick masses around the edge of the lake. These masses, dying and banking up, form

Jan 1, 1905

By T. A. Rickard

Clement Le Neve Foster was born at Camberwell on March 23, 1841, his father being Peter Le Neve Foster, who was secretary of the Society of Arts for 26 years. As a boy of 12 he was sent to school at Boulogne, receiving a preliminary education there; and in 1857, when only 16 years old, he took his degree of Bachelor of Science from the University of France. In October of the same year he returned to London and entered the Royal School of Mines, which was then in Jermyn Street. He distinguished himself by winning a scholarship and a medal, and by securing his degree as Associate of the Royal School of Mines in the abbreviated period of two years. This was followed by a year at the Bergakademie at Freiberg; subseque1:tly he visited several mining districts in Germany and Hungary. On returning to England, in November, 1860, he received from Sir Roderick Murchison an appointment upon the Geological Survey. During five years he was engaged in field-work, first on the Wealden beds in Kent and Sussex, and then in Derbyshire and Yorkshire. At this time his evenings were largely devoted to reading for a degree from London University. In 1861 he matriculated, obtaining the Bachelor of Science in 1863, with honors in biology and a University scholarship in geology; in 1864 he passed the two examinations entitling him to the Bachelor of Arts degree, and in 1865 he received the degree of Doctor of Science. In 1865 he succeeded Mr. Richard Pearce as lecturer to the Miners' Association of Cornwall and Devon. At the same time he became the curator to the museum of the Royal Geological Society of Cornwall at Penzance, a member of the council in 1873, and a life-member in 1874; he made frequent donations to the museum, besides contributing several valuable papers to

Jan 1, 1905

By Walter Wood

The specifications for cast-iron pipe that have been submitted at this meeting are practically the outgrowth of those which were originally adopted, about 1860, by Mr. Kirkwood of Brooklyn, N. Y. They have been changed but little since that time, the mode of testing pipe in the hydraulic press, as well as the method of coating, not having departed from the original practice. The chief addition to the specifications has been in the adoption of a test-bar 2 in. by 1 in. in crosa-section, broken between 24-in. supports by a transverse strain applied on the flat side. Test-bars were first introduced into pipe-specifications about 1870. At that time a satisfactory test-piece had to stand a tensile strain of 16,000 lb. per square inch. The present test-bar was adopted in order to give some idea of the deflection of the iron that was being used. These deflection-tests have been so satisfactory to both engineers and manufacturers, and have met the requirements of the pipe-trade so accurately, that it is considered best to hold to the . 2-in. by 1-in. bar instead of adopting the short " Arbitration Bar," which yields but little information from the stand-point of deflection. The new feature in these specifications is the effort to reach standards to which pipe shall be cast in the future, thus permitting the manufacturer to make up stock and the purchaser to find material on hand when he asks for deliveries. Heretofore there has never been ally standard weight for pipes? although in some sizes certain weights are more frequently asked for than others. The fixing of standards for pipes permits the adoption of definite standards for fittings. It has been aimed to secure such uniformity for fittings as will permit the same class of fittings to cover two or more classes of pipe. In order to accomplish

Jan 1, 1905

By John F. Allan

This paper does not pretend to advance any facts or improvements not known to many members of the Institute, but is intended merely to give a few practical hints on preliminary tests, and to call attention to a possible enlarged field for the cyanide process in the treatment of some silver-ores, which merits investigation. Broadly considered, the choice of a process for the treatment of silver-ores in Mexico is confined to the following alternatives: (1) Concentration for treatment by smelting; (2) milling and pan-amalgamation; (3) the patio and Ortega process; [4) chloridizing roast and lixiviation; (5) chloridizing roast and cyaniding; and (6) cyaniding of the crude ore. These methods of treatment may also be combined, and cyaniding or concentration, or both, may be introduced, at what-ever stage it is found to be most advantageous. The characteristics of the ore (especially its gold-content) and local conditions, such as distance from railway, cost of fuel, amount of water available, vary so much that it is impossible to make general comparisons between the different processes, either as to extraction or cost. Concentration and subsequent smelting may be made very expensive by long-distance transportation of concentrates; pan-amalgamation is undoubtedly expensive; and the patio process is barred when the ore contains appreciable amounts of gold, by reason of its poor extraction of that metal; yet there are many ores for which each of these processes is especially adapted, and the expense of treatment is compensated by the results obtained.

Jan 1, 1905

By Richard Moldenke

AmonG the things that will always remain to the credit of the foundry-industry is the circumstance that nearly all the research-work of practical value in daily routine was done by active foundrymen, and the results were freely given by them to the world. Moreover, while consumers felt that to them was due a more systematic and exact method of work, the foundry-men again were the first to act in the establishment of specifications under which their product should be sold. To come to more recent times, the American Foundrymen's Association has not only made an elaborate series of tests on cast-iron, and adopted tentative specifications based upon them, but, in addition, it has urged the International Association for Testing Materials, through its American representatives, to make the testing and specification of cast-iron a distinct issue. The half-hearted support first granted was greatly augmented by the rapidly-growing recognition accorded to the enormous iron-casting industry; and when the president of the American Society for Testing Materials was instructed to ask for a special commission for this purpose, Europe was ready to cooperate. During the Buda-Pesth congress, at, which America was represented by Prof. Howe, Mr. Wood and myself, it was decided to add five members to the general committee on steel and iron, whose special duty should be to conserve the interests of the cast-iron branch of the industry. America took up the work at once, and enlarged its committee to 67 members, all of whom were actively concerned in the manufacture or study of cast-iron in all of its branches. At the organization-meeting in Philadelphia, April 25, 1903, Mr. Walter Wood was elected chairman, and myself secretary; and, within a week thereafter, the sub-committees were appointed and became active at once. The scope of the work was naturally limited to those branches of the iron-casting in-

Jan 1, 1905

By James Gayley

The atmosphere, which plays such an important part in the manufacture of iron and steel, is the most variable element involved in its several processes; and particularly is this true of the blast-furnace process, which consumes air in large quantitiee. At no time since the blast-furnace became an important and widely used apparatus—even when it was operated in the most crude manner—have the variations in composition of the raw materials used been as frequent and as great as the variations in humidity of the atmosphere. Important improvements have been made in the blast-furnace and its accessories, such as the hot-blast stoves, the increase in size and change in the shape of the furnace, more efficient blowing-engines, the increased protection given to the bosh-walls, and the careful preparation of the raw material, all of which have exerted a pronounced influence on the furnace-operations from a metallurgical standpoint. But during the past eight years little advance has been made in this direction; the fuel-consumption has not diminished, nor has there been any material increase in production. Within that period, however, there has been witnessed the greatest development in appliances for the economical handling of material. So complete has been the work in this direction, that, except in isolated cases, in this country at least, a further extension does not hold out much promise of a satisfactory return on the investment required. It seemed that, with the exception of the gas-engine, we had about reached the limit, for like a strong wall, the atmosphere, with its humidity as variable to-day as when first blown into a primitive blast-furnace, appeared to stand as a barrier to

Jan 1, 1905

By W. A. Barrows

Mesabi ores differ from all other soft hematite-ores of the Lake Superior region in having but little or 110 binder. When exposed to heat, instead of baking into lumpy masses as do the Gogebic, Menominee or Marquette fine ores, they are changed to a sandy powder; and the finer particles, having little or no tendency to adhere together in the furnace, are carried by the ascending gas-currents into the down-comers and gas-mains forming flue-dust of a fine gritty nature. The term " finer particles " is used in this paper to mean ore fine enough to pass through a sieve with 80 meshes to the linear inch. Ore coarser than this is not likely to be carried over except in case of a slip, or an explosion in the furnace. The higher the percentage of fine particles in an ore from this range, therefore, the greater the amount of dust likely to result from its use. This statement, however, does not hold good in case of fine ores from the other ranges, and ores from the older ranges, carrying as high as 20 per cent. of material fine enough to pass through a 100-mesh sieve, have been in successful use for years, and have left no records of their causing trouble in furnace-practice by dust, slips, or explosions, so common since the introduction of Mesabi ores. Mesabi ores containing less than 12 per cent. of material which will pass through an 80-mesh sieve are considered of good structure; from 12 to 18 per cent., fair structure; and more than 18 per cent., poor structure. It was at first supposed that all these fine particles were carried over when the charge was lowered into the furnace, or during a slip, but the presence of partly reduced iron oxides in the flue-dust, even when no slip has occurred, proves that a part of the dust at least must have been low enough in the

Jan 1, 1905

By Charles H. Jones

Jan 1, 1905

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

By William P. Blake

Travelers in the desert regions of the southwestern portion of United States, especially along the valley of the Colorado of the West, can hardly fail to note that most of the rocky outcrope of the harder rocks have a uniform prevailing blackness of the surface, in strong contrast with the normal color of the interior of the rock when freshly broken. For example, the granitic or gneissic rocks of Pilot Knob, below Yuma, are blackened beyond easy recognition. So also rocks upon the lower Mojave in California are so thoroughly blackened, as if painted, that ordinary gneiss can scarcely be recognized without breaking it so as to show the interior color and structure. The discoloration is not confined to the rocky outcrops in place, but is found upon boulders and upon the loose rounded pebbles which strew the surface of the mesas along the Colorado river. These fragmentary rocks partake of the general blackening.

Jan 1, 1905

By H. H. Campbell

Many attempts have been made to write a formula by which to calculate the strength of steel from its chemical composition, but most of these endeavors have failed because there were too many disturbing conditions. It is idle to collect from the pages of trade-papers, books, or the proceedings of scientific societies, a multitude of observations. The combination of such results will simply show that steel of the same composition will vary in tensile strength through wide limits—a fact that has been known for generations. That cold-working, overheating, and many another form of heat-treatment alter fundamentally the strength of steel, is ancient history, although it is only recently that the microscope has pointed out the road to an explanation of the phenomena. It mag be urged that the microscopic structure must betaken into consideration in any formula giving the ultimate strength, but from the standpoint of the present investigation this is unnecessary. We are trying to determine primarily, not what changes in ultimate strength may be made by variations in the condition of carbon, but what effect is produced by changes in the amount of carbon, when its condition remains constant. For such an inquiry, in order that the condition of the carbon should remain as nearly uniform as possible, it is essential that all testrpieces be made under the same conditions; and it is believed that the tests described in this paper satisfy that requirement. The investigations were made at the works of the Pennsylvania Steel Company, Steelton, Pa.; the ingots from which the tests were made were 6 in. square in every case; they were heated in the same furnace and forged at the same ham-

Jan 1, 1905

By H. C. Meister

THE zinc-smelting industry of the United States has grown very rapidly in recent years and bids fair to outrival that of all other countries in the future. On account of the geographical situation of the chief ore-supplies, the industry may be divided into two main groups, the eastern and the western. The eastern and older group includes the works of Pennsylvania, New Jersey and Virginia, which practically control their own ore-supply. The western group includes the works of Illinois, Missouri, Kansas, Wisconsin and Indiana, which do not control their own ore-supply, but are compelled to buy the ore in the open market. It is for this reason that the western zinc-smelting industry has been undergoing continual changes since its inception 40 years ago. During the early discoveries of lead- and zinc-ore in the lead- and zinc-districts of Wisconsin and northern Illinois, the zinc-ore (sinithsonite or " bone " as the miner calls it) had no value and was considered waste; but later, when this ore was found in large quantities, it attracted the attention of metallurgists, which finally resulted, during the early sixties, in the building of the Matthiessen & Hegeler Zinc Works at LaSalle, Ill., the pioneer zinc-works of the West. A few years later, zinc-ore was discovered associated with the lead-ore in Jefferson county, southeastern Missouri, which started the industry at Carondelet or South St. Louis. Still later, the discoveries of zinc-ore in the lead-ore region, first' at Granby and then around Joplin, lead to the introduction of the industry in the southwest Missouri and Kansas districts. At first the development of the industry was slow, but it progressed steadily and it is now one of the leading metallurgical industries of the middle West.

Jan 1, 1905

By B. F. Bush

THE coal-fields of Missouri, situated hi the northern and western portion of the State, are distributed, in whole or in part, over 57 counties, embracing an area estimated by Mr. Broad-head to be practically 23,000 sq. miles, including small detached beds and outliers in St. Louis, St. Charles, Lincoln and Warren counties in the eastern part of the State. This area includes about 8,000 sq. miles of Upper or Barren Measures, 2,000 sq. miles of exposed Middle, and 12,420 sq. miles of exposed Lower Measures. In a general way, the Missouri coal-field is bounded on the east by an imaginary line entering the northern part of the State just east of the 92c1 Meridian and passing across the State in a southwesterly direction to a point on the Kansas-Missouri line a little below the southern boundary of Barton county. An important part of the field overlaps this line and extends down the northern side of the Missouri river, under¬lying the greater part of Randolph, Howard, Boone and Audrain counties. In all, 34 counties produced coal during the year 1903. Fig. 1 shows the position of the coal-fields in Missouri. GEOLOGICAL FEATURES. The Coal Measure formations, all of the Carboniferous age, rest unconformably upon the rocks of the sub-Carboniferous or Mississippian series, and, in some cases, upon the rocks of the Devonian and Silurian ages. From their outcrop on the eastern and southeastern borders of the field, the Measures dip west to northwest at the rate of 10 ft. per mile, reaching a maximum thickness estimated by

Jan 1, 1905

By JAMES QATLEY

THE atmosphere, which plays such an important part in the manufacture of iron and steel, is the most variable element involved in its several processes; and particularly is this true of the blast-furnace process, which consumes air in large quantities. At no time since the blast-furnace became an important and widely used apparatus-even when it was operated in the most crude manner-have the variations in composition of the raw materials used been as frequent and as great as the variations in humility of the atmosphere. Important, improvements have been made in the blast furnace and its accessories, such as the hot-blast stoves, the increase in size and change in the shape of the furnace, more efficient blowing engines, the increased protection given to the bosh walls, and the careful preparation of' the raw material, all of which have exerted a pronounced influence on the furnace-operations from a metallurgical standpoint. But during the past eight years little advance has been made in this direction; the fuel-consumption has not diminished, nor has there been any material increase in production. Within that period, however, there has been witnessed the greatest development in appliances for the economical handling of material. So complete has been the work in this direction, that, except in isolated cases, in this country at least., a further extension does not hold out much promise of a satisfactory return on the investment required. It seemed that, with the exception of the gas-engine, we had about reached the limit, for like a strong wall, the atmosphere, with its humility as variable to-clay as when first blown into a primitive blast-furnace, appeared to stand as a Barrier to

Jan 1, 1905

By George A. Laird

I. INTRODUCTION. THIS old and once famous district played, through its enormous production of silver and gold, an important part in the history of the State of San Luis Potosi. According to a pamphlet prepared under the direction of the Governor of the State, Sr. Don Blas Escontria, and presented to the visiting members of the Institute during the Mexican meeting of 1901, this district is situated 20 km. east of the city of San Luis Potosi, in a range of mountains of moderate height, extending 135 km. N. and S., and 16 km. E. and W.; and the mineralized area hitherto developed is about 600,000 sq. m. The history of the district,. as given by the record dated 1778, and formerly kept in the San Francisco convent, says that it was discovered in 1575 by Sr. Don Pedro Irarte, and adds that the city of San Luis Rey de Francisco del Potosi received its name (in allusion to the famous Potosi mines in Bolivia) by reason of the remarkable productiveness of its gold- and silver-mines in the first period of their exploration, during which they paid to the Crown, as " quintos " (the fifth part of the product), $97,000,000, as appears from the accounts of the royal treasury. The amount of the quientos paid during the " bonanza period " of 80 years was $72,000,000. The larger sum first mentioned probably represents a longer series of years. But either will suffice to indicate the great wealth of the mines. In 1663, the decadence of the industry began with the caving¬ in of several mines, concerning which the record of 1778, al¬ready cited, says, in substance, that on Good Friday one of the owners in the enterprise, in view of the unfavorable prospect of a lawsuit in which he was engaged, set fire to the timbers supporting the underground galleries and workings of the San

Jan 1, 1905

By H. H. Campbell

MANY attempts have been made to write a formula by which to calculate the strength of steel from its chemical composition, but most of these endeavors have failed because there were too many disturbing conditions. It is idle to collect from the pages of trade-papers, books, or the proceedings of scientific societies, a multitude of observations. The combination of such results will simply show that steel of the same composition will vary in tensile strength through wide limits-a fact that has been known for generations. That cold-working, overheating, and many another form of heat-treatment alter fundamentally the strength of steel, is ancient history, although it is only recently that the microscope has pointed out the road to an explanation of the phenomena. It may be urged that the microscopic structure must be taken into consideration in any formula giving the ultimate strength, but from the standpoint of the present investigation this is unnecessary. We are trying to determine primarily, not what changes in ultimate strength may be made by variations in the condition of carbon, but what effect is produced by changes in the amount of carbon, when its condition remains constant. For such an inquiry, in order that the condition of the carbon should remain as nearly uniform as possible, it is essential that all test-pieces be made under the same conditions; and it is be¬lieved that the tests described in this paper satisfy that require¬ment. The investigations were made at the works of the Pennsylvania Steel Company,. Steelton, Pa.; the ingots from which the tests were made were 6 in. square in every case; they were heated in the same furnace and forged at the same ham

Jan 1, 1905