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By T. C. Clarke

The history of iron construction in this country well illustrates the three phases of thought described by Auguste Comte, the French philosopher. The first is the era of faith, when belief in the safety of structures rests on the authority of the designer. The second is the era of criticism, when plans of structures are analyzed with much mathematical skill, but the data upon which the chain of reasoning depends is assumed upon insufficient experiment. The third, upon which we are now entering, is a scientific era, which demands experimental proof. It also demands that this proof shall be derived from experiments made on full-sized specimens, such as are in actual use, and not upon toy models. Until the construction of the United States testing-machine, now at Watertown Arsenal, it was impossible to make such experiments with accuracy. We now have a machine in which we can test full-sized specimens of every part of a bridge or other structure that we want to use, and under the same conditions in which it is actually used. The next thing is to get money to make these experiments available. No private individuals can afford to do it, and even if they could, they might wish to keep the results to themselves. So that the next point is that we want money, and that, I believe, everybodly thinks we should ask Congress for. We want also, as has been said, some one who shall make a business of testing, and who has plenty of time. Persons who are employed in private business are too much in a hurry; they want to do a thing and get done with it, and then do something else; but government officers are entirely free from this feeling; time to them is of no account, and in experimenting that is the very element that is of value; it does not do to be hurried; the great thing is to get it right and to test your results, and go over it, again and again. And the experimenter who operates the machine must be some person educated up to the use of it. We then want a general advisory board who will indicate a plan of experiments, collect the results; and publish them. Some experiments were made the other day at the Watertown Arsenal upon full-sized

Jan 1, 1882

By W. R. Crandall

The southern gold-fields offer some of the most complex and trying problems encountered in mining; and their successful solution often means the success or failure of the particular enterprise involved. In vein-mining, where the values are scattered over large areas, making it necessary to handle a large tonnage of very low average grade, the successful solution has been found in some instances by a combined hydraulicking and milling; water under pressure being used as the mining agent, and also for transporting the broken material to the mills, and effecting in its passage a partial concentration of the product by washing out the lighter and looser dirt of the ore-mass. The placer-deposits of the South, which were the original localities from which gold was mined, have been extensively worked, and to any one now undertaking their development offer many difficulties. The antiquity of the industry in this field, which was the cradle (in fact, literally the rocker), in which the California '49-er was born, gives assurance that all the deposits available to water and natural drainage have been more or less extensively worked already, so that, as a rule, any placer-deposits yet remaining undeveloped may be considered to offer some difficulty beyond the ability of the " old-timer " to overcome.

Jan 1, 1897

Jan 1, 1941

Jan 1, 1887

By Robert Glass Cleland

THIS IS a history of a company whose roots run deep into the nation's past and whose field of operations has never been narrowly confined. The men who founded Phelps Dodge were men of initiative and imagination. They were men of strong convictions and upright character. They held fast to the simple virtues and traditions of the days when America was young. This heritage they passed on to their successors. From the very beginning, under such leadership, Phelps Dodge became a company of large affairs. It bought and sold, exported and imported, built factories and organized railroads, converted great forests into lumber, and operated coal and iron mines. Much of the iron, copper, and tin plate used in the United States for a generation was under its control. Its business abroad was extensive enough to warrant the organization of a separate partnership in England. Then, almost half a century after its foundation, the company began to substitute new activities for old and eventually transferred its major operations to the West, primarily to Arizona. The family partnership became a corporation. Exporting and importing gave place to mining and metallurgy. Phelps Dodge became one of the largest

Jan 1, 1952

Jan 1, 1939

Jan 1, 1949

By C. H. Hitchcock

A brief resiclence in Virginia hasenabled me to examine some of its crystalline strata, and a few hints, concerning their correspondence with similar rocks elsewhere, may be of service to those who are studying them. In comparing the crystalline rocks of Virginin and New England, we may first recall the similarity of their geographical position. They constitute a continuous belt, being traceable through the Highlands of New York and yew Jersey, Southeastern Pennsylvania, in the counties of Bucks, Montgomery, Philadelphia, Delaware, and Chester, and Marylund. Thus the Green Mountains of Vermont and the White Mountains of New Hampshire seen] to be topographically continuous with the Blue Ridge and Midland districts of Virginia. This tract of country has been termed the Atlantic area in distinction from the Appalachian territory, whose eastern limit is the great, Lower Silurian limestone valley extending from the St. Lawrence and Champlain valleys to Alabama. The Appalachian formations were studied by the brothers Rogers, forty years since, and found to refit, unconformably upon the western flank of the Blue Ridge, the oldest of the series adjoining the gneisses, followed westerly by the other Palseozoic members in a regular ascending order, to which numercial designations were applied—Number 1 being the Cambrian, Number 2 the Lower Silurian Iimeqtones, etc?. In Vermont the same conclusion Was presented in the State reports: the Green Mountains were said to possess the anticlinal structure, and to underlie the quartzites and limestones. Inasmuch as this Atlantic area is' topgraphically continuous from the Middle to the Northern States, and is unconformably overlaid upon the west side by the same succession of strata, the presumption ii very strong that the history of bath sections has been the same, and that the entire area is of Eozoic age. Cross sections, in both districts, illustrate the existence of gigantic overturns, causing the strata of 'the Appalachian region to dip to wards the Atlantic gneisses. To the beginner it would appearthat tile Silurian group must dip beneath the crystallines, and hence many of the geologists in the beginning of the study of the stratigraphy of this easters border of the continent believed that

Jan 1, 1882

As a service to its readers, MINING ENGINEERING is publishing the mineral industry portion of the 1957 list of Accredited Undergraduate Engineering Curricula in the United States. This list, revised annually, is issued by the Education Committee of the Engineers Council for Professional Development, and covers all phases of engineering education. The AIME is actively represented on ECPD, which was jointly organized by the Founder Societies and various other groups interested in the professional recognition of engineers. ECPD is merely authorized by its constituent organizations to publish a list of accredited engineering curricula for use as desired by those agencies which require such a list. It has no authority to impose any restrictions or standardizations on schools. (Date following school refers to year of initial accrediting.)

Jan 7, 1958

1. Any society of undergraduates at a technical school, comprising students in any branch of engineering, metallurgy, chemistry, geology, etc., may be recognized by the Board of Directors in its discretion as an Affiliated Student Society, and its name, together with the names of its President and its Secretary, may be published in the MINING AND METALLURGY of the Directory of the Institute. The members of such a society will not be named individually on the membership list of the Institute, but may at any time be proposed for election as associates or junior associates of the Institute, in the usual way. 2. Membership in an Affiliated Student Society, certified by the official representative thereof, and accompanied with suitable testimony as to character and qualifications, will have special, weight with the Membership Committee of the Institute, in its consideration of the proposal of a candidate for membership or for Junior membership.

Jan 1, 1923

By ALFRED D. FLIWN

ENGINEERING COUNCIL is not "about to die," as some persons are saying. Through a natural and foreseen reorganization, Council is entering a new stage of existence with enlarged power for usefulness. Its early constituents have made it possible for many more of their fellow engineers and men of other technical vocations -to take a- share in its activities, responsibilities and support. A new organization is being set up, but it is really a new embodiment of the same spirit of service. Another step is being taken toward the full acceptance by the technical professions of their obligation to the public and to one another for those services which can -be rendered only through effective organization. A brief retrospect is timely. Engineering Council was established in the spring of 1917, as a department of United Engineering Society in response to requests of its Founder Societies. .It followed various attempts of these societies to deal through joint committees with public questions affect¬ing engineers -and with inter-society affairs. These attempts had very limited results. In the new by-laws adopted by United Engineering Society, the purposes and-powers d-powers of Engineering Council were thus defined: "To provide for convenient cooperation between the four Founder Societies, for the proper consideration of questions- of general interest to engineers and to the public, and to provide the means for united , action upon questions of common-concern to engineers.

Jan 1, 1920

By H. V. Churchill

THERE are two distinct methods of combating corrosive conditions. The first and most popular method is to choose a surface or material which will give adequate service under the specific and general conditions which are present. The second is a control or modification. of the corrosive conditions to the end that metals and materials which would be attacked and corroded without such control or modification may be used. Under the first method of attack of the corrosion problem may be grouped such devices as the selection of metals or alloys which offer great resistance or the use of protective coatings such as paints, lacquers or metallic coatings. Such procedures are exceedingly useful. It is, undoubtedly true that most of the problems of corrosion will be solved by recourse to this first method of attack. However, it must be remembered that there are many conditions in which metals are used where the choice of the particular metal to be used must depend upon other factors than corrosion behavior. Some of the factors which may govern the selection of metals for specific use are the physical and mechanical properties of the metals. But there is another factor which is of prime importance and that is relative price. It is the pressure of these factors of mechanical properties, physical characteristics, and relative price that has acted as the stimulus for the second method of combating corrosion. The producer and user of various metals is confronted with the fact that because of mechanical properties, physical characteristics, or price, the use of a particular metal is desirable even though the corrosion conditions are adverse to the use of the metal. In many cases, the successful use of the metal may be made even though it is impossible to protect the metal by coatings. This is rendered possible by control or modification of the corrosive media.

Jan 1, 1929

By S. J. Aparo

After surveying the beneficiation techniques in the Florida phosphate field, it is apparent that optimum beneficiation of this ore is a difficult task. Due to continually changing grade, size distribution and basic nature of the ore, there appears to be no universal technique nor a single reagent entirely satisfactory for achieving optimum metallurgy under these dynamic conditions. Although no major change in the basic flow sheet has been made in the last 20 years, there have been many refinements of the process in recent years which have helped increase production, improve recovery, lower unit cost of operation and make the beneficiation of lower grade deposits economically feasible. Among the significant changes is the use of larger plants and equipment which has helped to increase production significantly. The use of cyclones has facilitated and reduced the cost of slimes removal in these large plants. There have also been several new approaches to the flotation of coarse phosphate that are mentioned in the text of this paper. Lastly, significant improvements have also taken place in the area of flotation reagents.

Jan 1, 1970

W. H. BASSETT, * Waterbury, Conn.-Manganese should not be expected to remedy all the defects that are due to poor melting practice. It is undoubtedly valuable in helping to eliminate porosity in many of the alloys. In the copper-nickel alloys, its use is becoming almost universal, for, beside helping to make sound castings, it tends to hold the carbon in solution in the solidified alloy. GWILLIAM H. CLAMER,? Philadelphia, Pa.-I have found that manganese copper is satisfactory for eliminating sulfur and that it works very well in the crucible and when you have reducing conditions; but in a large reverberatory charge, where the conditions are oxidizing, we were not able to eliminate the sulfur.

Jan 1, 1919

Jan 1, 1883

By T. Egleston

IF we may characterize the aim of metallurgists twenty years ago by any one point towards which their efforts were especially directed, we should say it was the idea of adapting '' waste products" to some useful purpose, while the energy of to-day seems rather to take the direction of so arranging processes as to have no "waste products." The iron-master of this decade no longer speaks of the waste gases

By Jacob Reese

longer and tougher. In the worst case I have observed, viz., two inches difference in circumference, this difference in hardoess, as observed from the cutting, was more marked than in the other cases. Tires are always grouped in sets by the manufactrlrers fiorn their knowledge of the chenlical camposit,ion of the steel, with an attempt to get those in one set which have the same degree of hardness, so that the wear shall be equal all around ; they succeed pretty well on the average, but I have been noting the exceptioiis. Jacob Reese, PittsHukQh, Pa. : I have been very much interested in the reading and discusion of Dr. Dudley's paper. As far as it selates to the data of work performed by the rails, and the determination of their physical and chemical properties, I have nothing but commendation of Dr. Dildley to express, as the investigation covered a greater range, and was performed with more care in detail, than any similar work which has come under my notice. But I beg leave to differ with Dr. Dudley in his conclusions. What are the factors of hardness? Are they not carbon, silicon, phosphorus, and manganese? Now it is an untlisputed fact among iuetallurgiml experts that pure carbon and pure iron make the best steel of all degrees of carburieation, and for all purposes. While carbon hardens, it also strengthens the metal, but silicon, phosphorus, and manganese, in hardening, make the metal also brittle, and are injarious in any amount. Carbon should be called a strengthener; and I claim that a steel rail made hard with carbon, with the other three hardeners absent or reduced to a minimum, will carry a greater tonnage than any of Dr. Dudley's soft rails. But until the basic process is put into operation in this country we cannot expect to produce Bessemer or open-hearth steel without the presence of silicon, phosphorus, and manganese, in consitlerable quautities, aod I greatly donht the possibility of reducing the perceutage of any of them by the prment practice without seriously diminishing the output, and correspondingly increasing the net cost of production; which is an important question, since the increased life of the rail may be more than balanced by its increased cost. I think that the soft rails performed a greater amount of work, because they contained a less amorlllt of silicon, phosphorus, and wangatwe (britlkrcr, if I may so term them), and that carbon does wt reduce the wearing capacity of rails. I believe that a rail made by the baqic process, with silicon, phosphorus, and manganese reduced to a minimum, and containing 0.60 carbon, will be stronger

Jan 1, 1881

Jan 1, 1939

By Manfred Schmellenkamp

During the lust half-dozen years, longwall mining has taken on a new look, much of which is due to the introduction of self-advancing roof supports from Europe. Here is a report on two longwall operations, one which started up in 1956, the other in 1962. It is a story of manually set, friction- type props us, the new European type; the story of an 18-ton per man-shift operation us one of 50 tons per man-shift.

Jan 6, 1963

OCHRE is a semimineral composed by Nature of earth and a tincture of yellow caused by a fumosity of lead ore. By itself it is a material without any [38] metal, although when it is used in smelting it helps to melt the harsh and sour ores of metals. I do not know that it has any other use, except to painters. Bole is also a red viscous earth which has a very astringent and drying nature. It has no very apparent smell or taste, and I think that the cause of its redness lies in the fumosities of iron ore, for it is a companion to this and is found in its mines. It is an efficacious medicine against any poison and in this capacity has an action like terra sigillata* or perhaps better. In

Jan 1, 1942