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By Douglas Bunting

With the gradual exhaustion of the upper veins in the anthracite coal-fields, the problem of mining at greater depths acquires increasing importance and demands the consideration .of a number of important factors, one of which is the greater earth-pressure and the consequent necessity of stronger support for the roof. Under the pillar-and-chamber system, almost exclusively followed in the Northen anthracite-field, the highest economy in mining is generally secured by leaving, on first mining, pillars only sufficient to support safely the overlying strata. As to the necessary size of such pillars, the opinions of mining experts are widely divergent. In establishing the width of chambers and pillars, the thickness of vein and its depth below the surface have received little consideration. For instance, it has been quite usual to work both overlying and underlying veins with the same width of chambers and pillars, when the lower vein was two and one-half times as thick, and twice as far below the surface, as the upper. In view of the generally-accepted theory that the crushing-strength of coal-pillars of the same base-area becomes less with increased height, it is probable, in this instance at least, that the moat economical mining has not been secured. This question of adequate pillar-support is economically less important down to about 800 ft. than at greater depths; and it is with reference to mining at these greater depths that the study of the subject here presented has been prompted. The necessity of leaving larger pillars, involving greater mining-costs per ton and also smaller yields per acre, is one of the troubles of deep working. To mine without leaving adequate pillar-supports will result, sooner or later, in a squeeze. Limited areas, it is true, have been mined at certain widths of

Jan 1, 1912

By Gram Curtis

The apparatus described below for the handling of plates upon their delivery from the rolls, embodies features believed to be of interest to those contemplating the building of new plate-mills, and also to such owners of existing mills as may be considering the improvement of their works. The points to which attention is called are the small space required for the finishing-end of the mill, and consequently the very moderate size of the building for the amount of plates handled; the directness and ease of manipulation, and therefore the mall amount of labor required; the distribution of plates; the facilities and time allowed for their cooling. These, together with other features of detail and general arrangement scarcely less important, will become apparent when the descriptions and illustrations herewith given are understood. As these devices deal with the finishing of the plates only, they may be added to any plate-train when the floor-space and the building are large enough to permit their introduction; and it will be obvious that the features of this method, more or less modified, are applicable to any existing mill. Figs. 1 and 2 show a three-high 32-and 19- by 120-inch Lauth mill, with hydraulic lifting-tables, served by four heating-furnaces, with hydraulic cranes for charging and drawing. Upon leaving the rolls, the plate is allowed to rest with its forward edge projecting somewhat beyond the end of the catcher's table. Here it is seized by the automatic tongs, A, suspended from a buggy travelling in the overhead trough, B, and actuated by the hydraulic cylinder, C. These tongs are operated by a boy, who stands several feet from the heated plate, and controls the long light handle, D, shown in the plan, Fig. I. His duty is merely to advance the tongs by means of .the hydrulic cylinder, C, to raise or

Jan 1, 1892

By Alan M. Bateman

POSSIBLE postwar trends of the more important world minerals will be determined in part by their present world position and by the acts and forces that have operated during the war period, so it is desirable first to review briefly what has been happening in the foreign field of metals and minerals. When we first entered this war we of the mineral profession were all acutely conscious of our lack of strategic minerals and other materials, which had to be imported in great quantities-minerals such as manganese, chrome, tin, mercury, nickel, and antimony. But we realized also that we had to acquire vast quantities of those minerals of which we had thought we were bountifully supplied. Our assumed domestic abundances turned out to be woefully deficient, and demands also arose for new minerals never before produced in large quantities. Some threescore minerals entered the strategic list of our imports. Ores from new sources had to be sought, developed, and transported. Tonnages in the millions of such bulk materials as zinc, lead, copper, chrome, and manganese flowed to feed our war efforts. Sparsely distributed minerals such as tin, mercury, antimony, tungsten, cobalt, mica, and corundum had to be lured from their rock lairs in greatly increased quantities to feed the hungry maw of war industry, and the rare minerals such as tantalite, columbite, beryl, and quartz crystals had to be developed and procured in quantities never before dreamed of. New uses such as radio and radar created demands for many minerals formerly thought of only as adornments of museum collections and not as pressing industrial minerals. Such minerals were never before mined in quantity.

Jan 1, 1945

By R. A. Ritter, J. P. Batycky

A numerical technique has been developed to permit estimating the pressure gradient associated with laminar flow of thixotropic liquids through long Pipelines. For this purpose the pipeline is divided into a number of radial and longitudinal increments within which rheological properties of the fluid may be considered as constant at any time. Then, provided only that the fluid flow curve is defined at every duration of shear, it is possible to predict the instantaneous pressure gradient at any cross-section along the pipeline for each desired flow rate and pipe size. The technique consists of an iterative integration of shear rate to establish the appropriate value of the wall shear stress at each location. Consistency of fluid in the increment is determined by the flow history of that increment, while the radial flow associated with variations in velocity profile is accounted for by adjusting the width and radial position of the increment. A number of pressure profiles, computed at each of several flow rates, provide a convenient basis for pipeline design and pump selection. INTRODUCTION In recent years considerable attention has been given to predicting pressure drop associated with the isothermal laminar flow of time-independent non-Newtonian fluids in pipes and annuli. 6,11,12 The approach generally has been to develop analytical relationships between flow rate and pressure drop based on simple constitutive models which hopefully provide an approximate description of the rheological properties of the fluid. Analytical solutions are highly desirable since the influence of all pertinent parameters can be readily determined. Unfortunately, however, this approach is restricted to simple flow geometries and- frequently leads to erroneous results due to inadequacies in the model. In certain cases a solution may be obtained through applying appropriate numerical techniques.l,14 For example, a digital computer program is available for predicting the velocity profile and pressure drop encountered by any Newtonian or time-independent non-Newtonian fluid flowing under laminar conditions in a cylindrical pipe or annulus.l In this paper the consistency behavior of the fluid need only be described in terms of basic rheological data. Analyzing flow systems involving fluids with time-dependent rheological characteristics is considerably more complicated since substantial changes in consistency may occur because of sustained shear action. This sensitivity to shear frequently persists for several hours. Consequently, variations in pressure drop and/or flow rate resulting from the aging process and addition of unsheared or partially sheared fluid to the system must be considered for purposes of pipeline design. This paper outlines a numerical method for predicting the transient and steady-state laminar flow behavior of a thixotropic liquid in a pipeline of arbitrary length (i.e., at a specified constant flow rate, the instantaneous pressure gradient may be determined at any time after start up and at any location along the pipeline). Several such pressure gradient profiles, computed at several flow rates, may be combined to produce a complete portrait of the system response. This flow portrait provides a reasonable basis for pipeline design and for selecting a suitable pump characteristic. TIME-DEPENDENT RHEOLOGICAL BEHAVIOR The most familiar time-dependent rheological properties are those exhibited by thixotropic liquids. Many of these materials, particularly thixotropic crude oils, generally display an apparent yield stress in that a finite pressure gradient is required to initiate flow. Then, under the influence of sustained shear at a constant shear rate, the consistency systematically decreases to some final limiting value. The shear stress obtained at

By Yeatman, Pope

FOR many years geologists have felt that mining companies should adopt a more liberal policy in the publication of their reports. The increasing usefulness of the geologist to the mining profession in recent years demands that consideration be given to this question. Prior to 1900, the call for geologists of high reputation by mining companies was probably mainly in connection with lawsuits arising from the interpretation of rights or ownership as defined by the "Law of the Apex," and from problems such as finding the continuation of the vein or whether the vein followed was the main one or a branch. Later, outside of legal questions, the most intensive and general use of their services arose from the search for oil. Geologists to determine the position of the formations

Jan 1, 1938

Jan 1, 1922

Jan 1, 1941

By B. B. Cox

Iraq, formerly called Mesopotamia in Asiatic Turkey, became a kingdom under British Mandate after the world war and is expected to gain its independence in 1932 when it enters the League of Nations. The kingdom is shown on Fig. 1 in its relations to neighboring countries, to the Mediterranean Sea and to the Persian Gulf. It is slightly smaller than the State of Texas with its capitol, Baghdad, inland about as far from the Persian Gulf as Breckinridge, Tex., is from the Houston Shipping Channel. The oil fields lie 180 to 225 miles north of Baghdad, or about as far as from Breckinridge to Oklahoma City, and about as far from the Mediterranean as Fort Worth is from Hobbs, N. M. A narrow-gage railway runs from Basra, the Persian Gulf port, to Baghdad. From there another narrow-gage runs into the Kurdish hills east of the Tigris to Kirkuk. A standard-gage, part of the old Berlin-Baghdad system, follows the west bank of the Tigris northward from Baghdad to Baiji, a village about 100 miles south of Mosul. No railway exists between Iraq and the Mediterranean, though the Anatolian Railways in southern Turkey come to within 50 miles of the Iraq frontier and 120 miles of Mosul. Surveys have been completed for a railway through British Mandates from Haifa to Baghdad as well as for a railway through French Mandated Syria from Tripoli to Abu Kemal near the Iraq border. Wagon roads, excepting those constructed by the oil companies, are few and indifferent in Iraq and no road exists across the desert to the Mediterranean, but contrary to prevalent beliefs the surface is firm and free from sand dunes so that motor cars can go almost anywhere in dry weather, with ease. Frequent motor car and airplane service exists between Baghdad and the Mediterranean ports and motor car service may be had between Kirkuk and Nisibin, Turkey, where on two days each week through Wagons Lits service is available to Paris. Baghdad is about 21 days distant from New York City with present transport facilities. The climate is semiarid, similar to Imperial Valley, California, the average rainfall outside the mountainous parts amounting generally to

Jan 1, 1932

By G. S. Brooks, L. G. Duncan

During the past few years, the Mineral Point Zinc Co. has had under consideration the improvement of various types of gas-filtering apparatus used in the removal of dust from crushing and milling plants, in the manufacture of oxide, and on blast-furnace fume and sintering furnaces. The original equipment of the various plants of the company was, of course, along lines of the standard stationary bag house. These houses required large surfaces, hand shaking, and varied only in the manner of the collection of solids and in the distribution of the gas. , Early in 1908, the first trial of a mechanical bag house was made at Nassau Plant at Depue, Ill. The duty of this installation was on dust-laden gas from a fine-crushing mill. The Printz and Rau bag machine was finally adopted and put into operation. This ingenious machine embodied what were then to us two novel features in bag-house practice: 1. An intermittent crinkling and snapping of the filtering fabric to free the meshes of solids. 2. A reversal of gas flow for a short period by a temporary connection with the suction trunk. This equipment worked fairly well except in cold weather, when we ran into condensation troubles. Had we at that time understood more fully some of the limitations of fabric filtering work, these might well have been remedied. We were impressed by this experience, however, with the efficiency of sudden tension on the fabric under suction. After a study had been made of some of the western blast-furnace houses using the reversal-of-flow feature, experiments were started early in 3 914 with a view to developing an automatic equipment along the best lines of our past experience. The objects sought were: 1. Keeping labor out of the houses for hygienic reasons. 2. Reduction of labor costs. 3. Reduction in size of bag houses. 4. Accessibility. 5. Ability to handle relatively hot gases where required.

Jan 1, 1918

By C. F. Dietz

WHEN thinking of industrial relations, we must not confine the term to what is ordinarily called "welfare work;" viz., organizing baseball teams, departmental parties, athletic contests, and such things. These are all of interest but not very helpful in solving the problems of industry. We must think of industrial relations as that understanding developed between workers and management that permits of harmonious progress because of a mutual understanding of each other's problems. Most of the industrial unrest, discontent, mistrust, or antagonism is due to misunderstanding; and that misunderstanding is the direct result of not having taken the workers into our confidence. If they are merely cogs in a machine, employed to do certain things, and have no interest in anything but the receipt of the pay envelope, we cannot expect intelligent harmonious progress. There are still some people who think that the interests of management, or capital invested in a business, and the interests of the worker are diametrically opposed. That is an unfortunate belief; the interests are identical. If the worker does not understand what his part of the work represents, what the management's part represents, and what the invested capital's part represents, he is bound to have a misconception, of the matter and will think only in terms of the pay envelope. The methods used for producing a better understanding between workers and management do not much matter so long as the end is attained. Some plants prefer shop committees; others attempt to work through the foremen in the various departments; others, by personal contact-between the management and the men, especially if a shop is small. It does not really matter how the end is attained as long as the object is accomplished. The best type of industrial relations can probably be attained when the mystery is taken out of industry-when the workers understand what they. are a part of, what their function is, what they are contributing. They should also understand something of fundamental economics-that it is not just a question of getting all they can and giving just as little as possible but that their contribution makes for expansion, progress, and permanence, and opens a field of activity for themselves that other-wise would probably be blocked.

Jan 6, 1925

By Edward W. Parker

IF one is to place any credence at all in the reports published in the daily press, the subject of conservation has been a very lively topic of conversation during the past 60 days, and it does not appear that the temperature of the summer months has been in any way moderated by the discussion. It is a subject in which we are all vitally interested and to which, so far as our mineral resources are concerned, both the Institute and the Geological Survey have liberally contributed. The report of the National Conservation Commission, appointed by President Roosevelt, contains a series of papers on the conservation of mineral resources, all of which were prepared by members of the Geological Survey and were compiled largely from information previously collected by that Federal bureau in the performance of its regular duties. It is not the purpose of this paper to reiterate in extenso any of the material already published. The contributions of the Survey officials to the Commission's report have been published in a separate document as Bulletin No. 394. This docunient is for free distribution and may be obtained upon application to the Director of the Survey. In the preparation of this paper I desire merely to make a few suggestions regarding the possible necessity of some restraint upon or control of one branch of the mining industry with which I have been somewhat closely associated for the past 20 years-that of coal. Most of the members of the Institute are cognizant of the suits brought by the government against the anthracite-operators in Pennsylvania, or the combination of interests commonly known as the ? hard-coal trust." No defense of any illegal combination in restraint of trade is intended, but there are some facts which should not be lost sight of, and unfortu-\

Nov 1, 1909

By Robert Linton

AT its meeting on May 21, the Board of Directors approved the recommendations submitted by President Lovejoy and named a nominating committee for the year that is especially well distributed as to major technical interest and as to geography. As may be seen from the list published herewith, two come from the East, two from the Midwest, and three from the far West. Mr. Linton, the chairman, has been a valued member of the Institute for 36 years. A memorandum drawn up by Paul D. Merica, representing the A.I.M.E., and W. R. Barclay, representing The Institute of Metals of Great Britain, setting forth a reciprocal plan for special memberships in each Institute for members of the other, was discussed. Both societies already have formally approved the plan in principle and Dr. Merica was clothed with full authority to agree on a few small details that have not been settled, and conclude the arrangement in behalf of the Institute.

Jan 1, 1936

By Maynard H. Jameson

EARLIER investigations of the potential-drop-ratio method of electrical prospecting have indicated that under suitable conditions this method is well adapted to the location of formation boundaries in stratified ground. A description of this development was given several years ago by H. Lundberg and Th. Zuschlag.1 The curves published by these authors for the potential-drop-ratio variation above a horizontal contact indicated a definite relation of the position of the curve peak to the depth of the interface. The theory underlying this relation was subsequently studied by Z. Mitera in greater detail,2 and the theoretical deductions were compared with the results of tank experiments. The investigations available at this writing were confined to studies of horizontal formation boundaries. It is the purpose of this paper to extend the scope of the previous work to the problem of dipping layers. THEORY Consider the case of three media of different resistivities, whose interfaces are not parallel. If a point-source is located in one of these interfaces, its images do not lie in a straight line, but on the circumference of a circle whose center is at the hypothetical junction of the interfaces. R. F. Aldredge3 determined the relation that exists between the degrees of dip of the two interfaces and the distances between the various images and the point for which the potential is to be found. As seen in Fig. I, three media of resistivities po, pi, and p2 are involved, and the source I is located at the interface of the media (po) and (pi). The perpendicular depth of the lower interface is h,? is the dip, R is the distance between source I and potential point P, and r is the distance between the images and that point. To distinguish between images lying above the ground interface and those below, the notation "odd" and "even" images will be employed; images below the ground interface will be termed "odd" and those above "even." The following relations govern the distances between either kind of images and the potential point: [ ] As previously pointed out, the images of the source are on the circumference of a circle. If the angle of dip is ?, the angle measured from the horizontal to the first image is 2? to the second image it is 4?,, and so on. Since the limit of the reflecting interface is at its outcrop, the last possible

Jan 1, 1941

By Walter Miller

PETROLEUM refining, like other industries in the United States in 1940, focused much attention on its duties and opportunities in the field of national defense. In counter-distinction to the situation during the World War; the industry is well constituted as LO existing equipment, processes, and capacity together with planned additions to handle any demands that may be made upon it by the defense program needs. Evident throughout was the growing sense of ability to manipulate oil molecules for the production of materials not hitherto considered as being available commercially from petroleum The development and application of catalytically-induced reactions on a broad front is one of the distinguishing characteristics of refining progress during the year.

Jan 1, 1941

By R. H. Coats

MINING occupies a position of less importance than manufacturing or agriculture in Canada, but its relative contribution has increased greatly during the post- war period. Mineral production was only 5.14 per cent of the net value I of production of all kinds of commodities in 1919, but by 1936 the pro- portion had risen steadily to 12.76 per cent. Mining felt the depression, hut unlike agriculture, which is still ' sorely stricken, it has passed from early convalescence to complete recovery. For each of the last two years new high records were established for the industry as a whole and for the quantity of most metals produced. Mining has had a notable effect on - the growth of the power industry in Canada. Water power has been developed in the same or adjacent areas wherever mining camps have been 1 established, with few exceptions. Consumption of electrical energy by the mining industry gained 72 per cent within a decade, rising from 1604 million kw.-hr. in 1926 to 2754 in 1935. In. 1935 alone the mining industry purchased electric power

Jan 1, 1937

By Hermann Wedding

I ASK your permission to speak about a matter which is not of a specifically scientific nature, but more of a general-I might even say of an international-nature, and the international character which this city now presents must be my justification for introducing it. The Germans, very often, are thought to be an exceedingly warlike people, but I come to-day in the capacity of a peacemaker. Our German language is an original language; it is, therefore, a language in which it is impossible to change the meaning of a word at will. It may be, perhaps, easier in a combined language, as the English, to associate and to exchange meanings. Now, a word which we hear a great deal at the present day, is "Stahl," in English, "steel." This word means, in the German language, a substance which can be hardened. As the German literature, in relation to metallurgy, is the oldest of the modern world, this circumstance may give the German a right to ask for consideration. But I think, now, when the four languages, German, Swedish, French, and English, compete in rich metallurgical literature, it is very necessary to have uniformity in the nomenclature of iron, which would prove not only useful for science, but equally so for trade. For that purpose I propose to make the divisions of iron so that the word steel shall comprise a subdivision and not a primary division as formerly. Nature furnishes us iron mostly in the state of oxides, and if in any other condition, we must convert the ore into oxide before we can make iron. The oxides are always mixed with certain earthy substances called rock or gangue. The extraction of iron involves, therefore, the twofold process of the reduction of the iron, and im¬parting to it the amount of carbon necessary for technical purposes, and the separation of the reduced and carburized iron from the gangue. The reduction is always effected by carbon or carbonaceous substances (coke, anthracite, carbonic oxide, etc.), and the result is, according to the degree of heat employed, either malleable iron or a non-malleable iron. The process of making malleable iron in this way is called, generally, the direct process-in German, Rennarbeil. It produces the iron in a solid state with a fluid cinder. By this process our ancestors made all their iron, and it has been revived in various ways in modern times up to the process of Mr. Blair, so far as I know, always without commercial success. The

Jan 1, 1877

By R. E. Ogilvie, N. L. Peterson

Intevdiffusion and intrinsic diffusiorz coefficients were determined in the uranium-niobium system from diffusion couples analyzed with an electron microbeam probe. A Previously unveported intermediate phase, designated in this report as the delta phase, was found to exist along the mobium-rich side of the miscibility gap. Its composition width was determined from the concentration gradients in the diffusion couples. The presence of this phase was also confirmed by microhardness analysis and metallographic observations. THE excellent corrosion resistant properties, high-temperature strength and reasonable nuclear properties of niobium have prompted its use as an alloying element with uranium and as a possible cladding material for reactor fuel elements. Hence the formation and growth of intermetallic phases as well as diffusion data for the uranium-niobium system are of considerable practical importance to metallurgists and nuclear engineers. Diffusion zones may exhibit varying degrees of complexity dependi.ng upon the mutual solubility of the metals involved, and the intermediate phases which may form. In the simplest case where the metals exhibit a calmplete range of solid solubility, a single phase region is produced. Generally, however, the metals may react to produce a multiphase diffusion zone containing several layers of intermetallic phases. A number of investigatorsl-6 have analyzed the concentration gradients present in diffusion couples in order to investigate phase equilibria and solu- bility limits. If diffusion is the rate-controlling process in establishing a concentration gradient, the compositions at the interfaces of the intermediate phases will represent the equilibrium values expected from the phase diagram at the temperature at which diffusion has taken place. No published information is available at this time on diffusion in the uranium-niobium system. A number of investigators7-" have contributed information to the construction of the uranium-niobium phase diagram from other than diffusion techniques. There is good agreement on the high uranium side of the phase diagram, but the high niobium side of the miscibility gap still remains somewhat in doubt. The phase diagram as determined by B. A. Rogers, et al.7 is shown in Fig. 1. The present work was aimed at obtaining fundamental information about the solubility limits of the miscibility gap and diffusion in the uranium-niobium system. A Kirkendall effect, which might be expected on the basis of the rather large difference in melting points between uranium (1132°C) and niobium (2415" C), was also investigated. The concentration gradients were measured by an electron microbeam probe technique, similar to that used by Castaing,l2 Adda and philibert,13, l4 and Macres.4

Jan 1, 1961

By R. A. Esmonde

This paper describes the building and testing of a prototype welded aluminum truck body to a new design concept. The results of these tests are given along with an outline of further developments in the design and field application of aluminum bodies. The results of field service history are recorded with special reference to types of mining operations, service performance, wear, maintenance and economics of operation. Mention is made of current U.S. usage and predictions given as to future development of aluminum bodies in the mining industry. The use of aluminum for off-highway truck bodies in hauling rock for the mining and construction industries is by no means the novelty that it may seem. In 1932 an aluminum unit proved very satisfactory in service on the Hoover Dam project but at that time the only high strength aluminum alloys available were not weldable and with the high cost of construction, a sound economic case for an aluminum body could not be made. After World War I1 great advances in aluminum welding techniques, using the inert gas shield, combined with the development of high strength alloys with good welded properties and welding characteristics changed the whole picture. Welded aluminum bodies were rapidly developed and by 1958 attention was again focused on the use of aluminum for off-highway truck bodies. EARLY DEVELOPMENT WORK In 1959 Alcan, the Aluminum Co. of Canada, embarked on an extensive development program to prove the durability and economics of aluminum truck bodies for the mining and construction industries. The first step was to design a prototype aluminum body which took particular advantage of the fact that the modulus of aluminum is only one third that of steel. This means that within the elastic range, aluminum moves three times as much as steel which makes it more flexible and capable of absorbing much greater impact shocks. A body was built and mounted on a 22-ton truck and taken to the Jeffery Mine of Canadian Johns Manville Company at Asbestos, P.Q., Canada. Very little information was available as to the order of stresses that were set up in off-highway truck bodies and so it was therefore decided to carry out a test program to find out this information.

Jan 1, 1969

By C. E. BOCKUSD

WHEN Mr. Bain asked me to lunch with you he requested that I say a few words as to how the Institute could be helpful to the bituminous coal industry. I feel like saying, "Thank you, what have you?" I do not want to trace in detail the story that is old already to many of you. On the other hand it does take some little stage-setting to illustrate what is the matter in the bituminous coal industry, a trouble that must some day be cured. There has been something over a century of bituminous coal production as a real business in this country. True, Joliet and Marquette discovered coal in Illinois in 1673, according to published accounts of their travels, and shortly thereafter Father Hennepin also found Illinois coal in 1689. Coal was mined near Richmond in 1750, and Richmond shipped coal to New York and Philadelphia in 1789. But it was not until 1838 that the production of bituminous coal in this country totaled a yearly output equal to the minimum for one class A mine today, for that was the first year that production exceeded 200,000 tons.

Jan 1, 1930

By John W. Cahn, John E. Hilliard

Single crystals of copper and silicon-iron were cold rolled in orientations chosen to produce individually the major components of the poly crystalline deformation texture. The orientation dependence of the recrystallization kinetics was studied relative to the primary recrystallization textures of these specimens. It is not possible to rationalize the poly crystalline re crystallized textures on this basis. The results suggest an important role of the interaction of adjacent crystals during the deformation of aggregates. BRICK and Williamson1 first noted evidence that the recrystallization temperature was different for straight-rolled and cross-rolled copper given comparable reductions. Michalak and Hibbard2 investigated quantitatively the effect of rolling procedure on the kinetics of recrystallization of cold-rolled copper and found that material cold-rolled the same amount by straight-pass, cross-pass, and compression-pass techniques developed different deformation and recrystallization textures, different 1-hr recrystallization temperatures, and different recrystallization kinetics. However, the temperature dependence of the rate of recrystallization was essentially the same for all techniques. Similar results were obtained on iron. Dunn and Koh3 in studying the recrystallization textures of cold-rolled silicon-iron single crystals reported large differences in the annealing temperatures and times required to recrystallize specimens of different orientations cold-rolled the same amount. Liu4 and Liu and Hibbard5 utilized the concept of different recrystallization temperatures for different orientations of cold-rolled crystals to rationalize the difference in recrystallization textures found in various face-centered-cubic metals. Their explanation predicted a significant difference in the recrystallization kinetics of deformed (110) [112] crystals as compared to (358) [352] crystals, and, in fact, Liu4 reported evidence that this difference existed at least qualitatively. Verbraak6 who rolled and recrystallized a series of copper single crystals found that the double (112) [111] rolled orientation is related to recrystallized cube texture formation. The effect of rolling intensity on the relative amount of cube component suggests an important role of recrystallization kinetics. Walter and Hibbard7 while trying to relate the behavior of rolled and recrystallized single crystals of silicon-iron to the behavior of polycrystal-line silicon-iron again noted that differences in recrystallization kinetics were necessary to rationalize their results. The purpose of the present investigation was to obtain quantitative kinetic data on the recrystallization of single crystals of both copper and silicon-iron rolled to initial isolated individual orientations corresponding to those found in the polycrystalline deformation textures. These data might indicate the importance of the deformation orientation, i.e. the range of available nuclei, the deformed matrix orientation into which these nuclei grow, and the orientation dependence of their growth rate during primary recrystallization on this texture. I. COPPER Experimental Procedure—A single crystal of 99.98 pet purity copper, grown by the Bridgman technique, was purchased in the form of a bar 1 1/2

Jan 1, 1962