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By C. W. Purington

Jan 1, 1900

By Zay Jeffries

Jan 1, 1930

By Carl Henrich

Jan 1, 1890

By P. Barnes

Several statements have been made to the Institute, somewhat detached from each other, as to the cost of some parts of these works, but they have not included any extended description of the buildings or machinery. The general plan of the work connected with the water supply differs, in some important details, from that which has been common either in the Pittsburgh district or elsewhere, and a somewhat extended description may be of interest to the Institute, in connection with a note of the cost of the work. The plan as a whole, and nearly all the important details, were developed by Mr. William P. Shinn, C.E., the general manager of the Company. The immediate and responsible charge of the work was in the hands of Mr. John C. Lewis, C.E., to whom had been committed all the work of this general description, including the laying out of the whole of the foundations, the erection of the buildings, and the grading and laying down of the entire railroad system. The continuous operation of the machinery and other fixtures of these waterworks, for more than three years, has fully demonstrated the correctness and econonly of the plan adopted. No casualties of any moment have befallen the apparatus, and no improvements have been suggested as important except that the gate at the river end of the conduit should have been made more completely water-tight, so that the whole length of the conduit could be pumped out dry without resort to any temporary dam in the conduit itself. In general terms the works of the Edgar Thomson Company are situated on a plateau, about 52 feet above the low-water level of the Monongahela River, and about 2000 feet from its bank. The site of the works is bordered on one side by Turtle Creek, a small stream which drains a considerable area of coal mining territory. This creek is about 100 feet from the group of buildings which have been erected, but it flows into the Monongahela River at a point, about 1200 feet further up than that selected for the entrance to the waterworks conduit. It was ascertained by analysis that the water in the creek contains an important percentage of sulphate of lime, while the water of the river is of unusual purity, in respect of any salts

Jan 1, 1879

By C. J. Frosch, J. A. May, H. G. White, C. D. Thurmond

Gallium phosphide epitaxial layers were grown from the vapor phase on undoped single-crystal galliurn arsenide substrates in silica tubes by an open-tube wet-hydrogen process. The epitaxial layers were grown over a range of water pressures at three substrate temperatures. Excess donor concentrations were determined by surface barvier capacitance measurelrzents without removing the layers from the substrates. The excess dmlor concentration, ND-NA, is fo~ind to vary approxilnately inversely with the pressure of water added to the hydrogen carrier gas. This is the relationship that would be expected for singly ionized silicon donors on gallium sites in extrinsic galliunz phosphide, with the silicon coming from the SiO generated by the reaction of hydrogen with the silica tube. An increase in the partial pressure of water in the hydrogen stream decreases the SiO pressure. The results indicate that ni, the intrinsic hole and electrmt concentration for gallium phosphide at the three substrate temperatures, is smaller than the concentration estimated from available data for the density of states effective masses and the energy gap. Mass-spectrographic measurements confirm that the dono?, introduced into gallium phosphide is silicon. The equilibrium concentrations of silicon in vapor-flown gallium Phosphide have been estimated from available thernzodynamic information that includes the solubility measurements of silicon in gallium phosphide in equilibrium with a gallium-rich liquid phase. Satisfactory agreement with the measured silicon concentrations is obtained. FROSCH1 has described an open-tube process for growing single-crystal Gap from the vapor phase by a GazO transport mechanism. The method depends upon the reaction of H20 in an H2 carrier gas with a heated source of polycrystalline Gap which provides the necessary vapor species. When the temperature of these vapor species is lowered, super saturation occurs and single-crystal Gap will deposit on a suitable substrate. Unintentionally doped single crystals of Gap grown by the wet H2 process in silica tubes are n type. Evidence is presented to show that the donor introduced is silicon, and that a qua si-equilibrium model accounts for the inverse dependence of the donor concentration on the water partial pressure and predicts the magnitude of the donor concentrations. Ainslie et al. experimentally showed a similar inverse relationship between the carrier density and oxygen pressure for GaAs. Emission-spectrographic analyses showed a decrease in the silicon concentration with increasing oxygen overpressure for GaAs. Cochran and Foster suggested the theoretical possibility of suppressing silicon contamination by using Ga20 generated by the reaction of gallium with water vapor. 1) EXPERIMENTAL The apparatus and procedures are essentially the same as those described by Frosch.' The apparatus consists of a 25-mm-ID SiO2 tube extending through a controlled high-temperature flat zone for the location of the polycrystalline Gap source and a downstream temperature gradient falling at a rate of about 14°C per cm. The latter provides the region of super saturation for the location of the single-crystal substrate. The partial pressure of water in the inflowing hydrogen stream, pA2, O was controlled by mixing me-tered proportions of dry H2 with H2 saturated with H2O vapor at 0°C. The total gas flows were about 200 cu cm per min in all experiments. The Gap sources were prepared by pulverizing boat-grown polycrystalline ingots to pass a 20-mesh sieve. The substrates were cut from an undoped single-crystal boat-grown GaAs ingot purchased from Monsanto. This ingot had a carrier concentration of about 1015 atoms per cu cm, a resistivity of about 5 ohm-cm, and a mobility of about 5000 sq cm per v sec at 25°C. Substrates with dimensions of 1 by 1 by 5 x lo-' cm were employed. The growth faces were chemically polished (111) arsenic faces. Epitaxial layers, at least 7.5 x 10-3 cm thick, were grown,. This required from 1 to 24 hr depending upon the Pii2Q values and the temperatures. In all of the runs, the source temperatures were 50°C higher than the substrate temperatures. Samples were prepared

Jan 1, 1968

By Sidney Snook

FLUORSPAR production is the most important industry in a compact area in southern Illinois and western Kentucky bordering the Ohio River. Producers' activities do not usually figure much in the mining news of the country, so that few know that the last year or so has been an unusually active one. Mine shipments more than doubled in 1939 compared with the poor year 1938. The average price changed but little, though it is now about one-sixth higher than at the beginning of last year. The outbreak of war in Europe a year ago lent an immediate stimulus to the industry, though only about 15 per cent of the domestic consumption is normally imported, thanks to a tariff of $8.40 per ton, equivalent to about 30 per cent ad valorem. Be- cause of the increased production and many expansions and improvements in the mines and plants, the period since the beginning of 1939 has been the most important one for the industry in the last 15 years.

Jan 1, 1940

mean to say that these explosions are mechanical, but that the ejectment of the stock, throwing out of tops, etc., are mechanical. I see no reason at present, although I have had almost no experience in the use of large quantities of Mesabi ore, to change my ideas on the subject. That these explosions should follow irregular working or slipping in the furnace, I think can be explained. I have noticed that immediately following slips there is little or no settling of the stock on top, although there is no lessening of the volume of gas passing into the stoves and boilers. Supposing that, after a slip of 3 or 4 feet, the filling continues, but for some distance from the 'top the stock fails to move: there would be a much better chance for the deposited carbon to clog interstices in the stock, and for the additional effect in the same direction of the fine ore in the charge, than if the stock were properly settling. Under such conditions it is easily supposable that the openings would be entirely closed, or closed so tightly that the pressure below the obstruction would be raised to a point approaching the blast-pressure, or to a point high enough to force a passage or an enlargement of the small passages which may remain. When this occurs, gas from below under pressure carries with it large quantities of deposited carbon and fine ore; if the case is aggravated, coke, stone, bell, etc. As soon as the red-hot deposited carbon meets the air there are perfect conditions for a dust explosion, which naturally follows, the same as in a coal-mine or flour-mill.

Jan 1, 1899

By J. F. Kemp

The use of nickel-steel has directed increasing interest of late towards the deposits of nickel, and at the same time the parallel advance in our knowledge of the basic igneous rocks has rendered these deposits a subject of important geological inquiry. Investigations have led to some views, more or less new, on the igneous origin of certain ores, which, though not universally accepted, have a growing number of adherents. In Europe, the mines in Norway have been especially suggestive subjects of study, and others somewhat less generally known have also added their testimony; while in this country the great economic importance and scientific interest of the developments in the Sudbury district of Canada, have furnished the principal texts for the discourses that have appeared among us. The purpose of the present paper is to set forth these views through the medium of one interesting ore-body, of which but little has been written ; and, by the description of another, to place in contrast two different geological associations in which nickeliferous pyrrhotite occurs, and to indicate a generalization, based upon these different geological characters, and justified by the experience so far gained. To Prof. J. H. L. Vogt, of Christiania, Norway, is due the chief credit for the revival of interest in the geology of nickel. His important contributions* of recent date have made generally available

Jan 1, 1895

By C. A. Stetefeldt

It will be of interest to compare the statistics of the gas-producer plant at Aspen, Colorado (recorded by Mr. W. S. Morse in a paper read at the Montreal Meeting, February, 1893*), with those at the Marsac mill, Park City, Utah, where such a plant was first introduced by the writer in July, 1890. In both mills a Stetefeldt furnace is used for roasting; but the Marsac mill has the old-fidsdshioned revolving dryers, while at Aspen, shelf-dryers are at hand. At Aspen, separate Taylor-producers are provided for the Stetefeldt furnace and the shelf-dryers; at the Marsac mill one 7-foot producer supplies gas to both the furnace and the dryers. Hence, in the latter case, the quantity of coal consumed for each apparatus can only be estimated, based upon the relative consumption of wood before gas was introduced. According to Mr. Wilson's statement, the relative consumption of wood in the Stetefeldt furnace and the revolving dryers was as 3 to 2. In the year 1892 the Marsac mill put through the dryers and the Stetefeldt furnace the following quantities of ore and salt (approximate dry weights) : ore, 22,800 tons; salt, 2262 tons. There were consumed in the Taylor-producer 2,714 tons of Rock Springs coal. We may thus make the comparative estimate as follows: Table Showing the Consumption of Coal per Ton Of Ore and Salt at the Marsac and Aspen Mills. Marsac. Aspen. Difference. Pounds. Pounds. Pounds. Drying ore and salt,.... 86.63 72.22 14.41 Roasting ore,.....142.40 117.44 24.96 Total,.....229.03 189.66 39.37 In making a just comparison a number of items must be taken

Jan 1, 1894

By N. A. D. Parlee, I. D. Shah

THIS communication reports the results of some work done on the effect of gold, palladium, and platinum on the liquid-gas-solid equilibrium in the Ag-O system,1,2 see Fig. 1. Recently several investigators3, 4, 5 have reported the effects of gold, palladium, platinum, and copper on the solubility of oxygen in liquid silver. This communication represents only a portion of the work done here on the solubility of oxygen in liquid silver and liquid Ag-Au, Ag-Pd, and Ag-Pt alloyss—the greater part having already been reprted. The apparatus, materials, and procedures used were similar to those of earlier work.' l The main precautions observed in obtaining these freezing points at constant temperature and PO2 = 1 atm were as follows: 1) The points were approached very slowly from higher temperatures. 2) In the very near vicinity of the L-G-S equilibrium point precautions were taken to see that the melt was in equilibrium with oxygen at one atm. Equilibrium was considered to have been attained when no more absorption of oxygen was observed in the last 15 min at a fixed temperature. 3) In the case of these alloys, the freezing point of the melt at 1 atm of oxygen and the equilibrium amount of oxygen absorbed by the liquid "infinitesimally" above this point were determined by lowering the temperature in very, very small steps, equilibrating at

Jan 1, 1969

By John W. Langley

In the summer of 1888 it was the fortune of the writer to present the subject of the desirability of establishing a set of samples of steel, which should be analyzed with extreme care, in order that they might become standards to which scientific and commercial analyses of iron and steel could be subsequently referred; also, that greater uniformity in the results of analyses might be brought about, since these standards would bear towards analytical methods somewhat the position which the original units of weight and length, the gramme and meter, or the pound and yard, preserved in Paris, London, and Washington, do to the mechanical arts. The plan met with hearty co-operation, with the result that com mittees were appointed in Sweden, Germany, France, England, and America, to receive the material and to see that the necessary au alyses were executed. In England, the British Association for the Advancement of Science appointed a committee, which subsequently published a plan

Jan 1, 1891

By Robert W. Hunt

THE first pump of this character, made by H. R. Worthington, and, so far as the writer is informed, the first and only one of this kind ever constructed, is now in daily use in the above-named works. The water-pressure necessary for the working of the hydraulic machinery of this plant had been supplied, up to the time of the building of this pump, by two Worthington Duplex High Pressure Pumps, having steam-cylinders of 20 inches diameter and 12-inch stroke, with water-plungers of 72 inches diameter; eight inlet and eight outlet valves of 22 inches diameter, and pumping into a 6-inch pipe. These pumps required a large amount of steam, and, in consequence of the various additions to their duty, their capacity became far short of the work required. In preference to putting in another engine of the same class, it was decided to accept Mr. Worthington's proposition to build the compound one under description, he guaranteeing that it should be equal to the demands of the works, and at the same time cause a saving of from 5 to 6 tons of coal per day from the amount required to run the two old pumps. The new engine has been in operation about one month, and so far has exceeded the most sanguine expectations. It consists of two high-pressure cylinders of 21 inches and two low-pressure ones of 36g inches diameter, by 36-inch stroke, with water-plungers of 91 inches diameter. There are two air-pumps of 20 inches diameter by 18-inch stroke; the condenser being 24 inches diameter by 60 inches high. Both cylinders are jacketed with wood and felt, and the low-pressure cylinder also with live steam. The high and low pressure steam-cylinders are in line and immediately adjoining each other, while the inconveniences attending an internal stuffing-box are avoided by having two piston-rods for each of the low-pressure cylinders, running through stuffing-boxes on the outside of the smaller high-pressure ones. The steam-valves are very ingeniously designed balanced

Jan 1, 1876

By Henry D. Hibbard

Henry D. HibbaRd, Pittsburgh, Pa,: This is a most interesting and instructive paper, some of whose lessons should find immediate application. It points out how fuel-consumption is to be decreased in open-hearth practice, by changes in the plan of the furnace. To look first at the greatest item of loss, radiation, it is seen that thicker brick-work is advisable to lessen this. Especially is this true of the roof, made at present, almost universally, only 9 inches thick to prevent cutting. Now that high roofs, well above the course of the flame, are becoming general, and the average melter is better able to judge the temperature of his furnace, that reason has less force; and we may build roofs 18 inches thick, or perhaps better cover the usual 9 inches with an equivalent layer of sand, which has the advantage of following the arch as it rises and falls with the different degrees of heat. The side-walls of the hearth, usually 131/2 inches thick, may also he thickened up to 18 inches, and the door-linings to 7 inches; and the heat thereby saved will be valuable, while its absence from the working-platform will be much appreciated by the workmen.

Jan 1, 1892

By Francis T. Christy

One aspect of ocean mining that is frequently overlooked in discussions is the problem of establishing some form of legal control over the seas. Much of the discussion centers on mining in territorial waters, which are controlled by the various countries according to the Geneva Convention on the Continental Shelf, and perhaps by political subdivisions of countries such as the individual states of the U.S. But as technology improves and the mining of deeper waters becomes feasible, the problem of rights outside the continental shelf and territorial waters becomes a significant factor for anyone expending the time and capital for development. Several schemes are possible for regulating ocean mining but as yet none have been instituted, except what might be termed the "wait and see" approach. Even some of the coastal states in the U.S. have no regulations governing mining in the territorial waters under their jurisdiction. Until some regulation is formulated, there may well be little development in ocean mining due to the high risk of capital involved, both with respect to companies wishing to invest their own funds and financial institutions funding a venture to develop offshore mineral deposits.

Jan 7, 1968

By P. Barnes

Some statements have already been made to the Institute in reference to the cost of other departments of the above-named works, and some details have been given in tabular form.* For the purpose of the present paper it may be sufficient to say that this converting works is made up of three buildings, a cupolahouse, an engine-house, and a converting-house. The machinery and fixtures comprise two blowing-engines, two pressure-pumps, two five-ton converters, five hydraulic cranes, three pig-iron cupolas, four spiegel cupolas, two lifts for the cupolas, together with the usual arrangements of smaller parts. Every effort was made in the construction to combine efficiency of operation with durability, and the general course of the operation of the works during two and a half years seems to warrant the belief that the large outlay has been fully justified. * In the accompanying tabular statement all items on vouchers less than ten dollars, and all freight items have been omitted.

Jan 1, 1879

I HAVE previously demonstrated to you as well as I knew how in what way ores are treated and then how the separated metals are brought to their pure and ultimate limit of perfection by means of smelting and other artificial fires; all except gold, which remained incorporated in the silver. Because the method used for the others does not serve for this, and if indeed it did serve it would be a great labor and could not be done without a great loss of the thing, it is therefore necessary to proceed with the practice of another art if you wish finally to extract gold from the bonds of the intrinsic substance of silver, for it exists bound and scattered in this like the soul in the body of living creatures. In this, unlike the other works where you make direct use of the vigor of the fire, you use a substance that is like water, drawn by the force of fire from a very powerful composition of two materials. This is a very marvelous thing to consider as a liquor because of its powerful effects. It is made by artificial distillations and it has an acid property and the power of corroding and reducing into itself silver and any other metal placed in it, with the exception of gold. Nothing is apparent in it except a pure water. It is indeed a very ingenious thing for which we must be greatly indebted to that philosopher, alchemist, or whoever else was its discoverer. The silver that contains gold is put in this water, and from its former quiet state you will see it change as if forced to combat and breathlessly devour and consume that silver in itself and change it into water. This happens in a very short time and with very little help from the heat of the fire. All the gold that was united in the silver you will see like sand at the bottom, and when the water is taken off by decantation it will freely give you all the gold without any loss. Nor is it so ill-mannered as to fail to restore the silver to its place if you wish; and though it seems to have consumed and spoiled it as it was before, it returns it to you without loss. Since the process of this art is a very useful thing for anyone who knows

Jan 1, 1942

By J. C. Williams, M. J. Blackburn

MANY aspects of the formation of the metastable w phase in titanium-transition metal alloys have been described in several recent papers.1-4 These papers have reviewed earlier work on the w phase and have further defined most of the important features related to the formation of this phase, e.g-., its crystal structure, composition, and morphology. There are, however, several important points regarding formation of the w phase in titanium alloys which have been described in less detail. Two of these are the relationship between lattice misfit and w phase morphology and the influence of lattice misfit on the mode of formation of the equilibrium a phase. In this communi- cation we will present transmission electron microscopy results relevant to these two points. The alloys used in this study were prepared by non-consumable electrode arc melting, each 30-g button being remelted a minimum of twelve times. The alloy compositions we have studied are listed in Table I. Thin foils were prepared using standard techniques described elsewhere. Two distinct c' phase morphologies have been reported in earlier papers. The phase is ellipsoidal in the Ti-Mo3 and Ti-Nbl system and cubical in the Ti-V3 system. Results of the present study show that the w phase is also cubical in Ti-Mn, Ti-Fe, and Ti-Cr alloys as illustrated in Fig. l(b) to (d). Fig. l(a) shows the ellipsoidal morphology in Ti-MO3 for comparison purposes. It was suggested in an earlier paper3 that the w phase morphology may be controlled by the lat-

Jan 1, 1970

By H. W. Schadler

The superplastic behavior of low carbon and manganese bearing steels has been evaluated. The results of elevated-temperature stress-strain rate and elongation tests are reported which indicate that high strain rate sensitivity (>0.5) and adequate elongations are achievable in ultrafine-grained steels 1 to 2 p, but at strain rates which are not commercially attractive. It has been demonstrated that the fine grain size is retained after long times and high strains if the temperature is kept within the range of the two-phase (a + ?) field. INTEREST in superplasticity has been stimulated by the desire to: 1) understand the origin of, and mechanisms responsible for, the large uniform elongations observed, and 2) exploit this property for commercial advantage in metal forming operations. Although the Zn-22 wt pct Al alloy presently being studied as a model material1-5 may find application in sheet forming and extrusion, the potential of super-plasticity should best be realized in large tonnage materials, such as steel and aluminum alloys. The degree of superplasticity in low-carbon and manganese-bearing steels has been evaluated. The results of elevated-temperature stress-strain rate and elongation tests on ultrafine grain size material are reported. Avery and Backofen6 and Hart7 have shown that geometrically stable flow leading to extensive uniform elongation in the tension test is associated with high values of the strain rate sensitivity, m, defined: Lozinsky had reported that titanium and zirconium experience permanent deformation if subjected to a constant load and cyclic heating through the temperature range of the phase transformation. Although strain rate sensitivities in excess of about 0.2 had not been reported previously for steel, permanent deformation had been observed11-13 in a wide variety of steels subjected to a constant load and cyclic heating through the temperature range of the a-? phase transformation. Thus by analogy, steel could be expected to exhibit high strain rate sensitivity but only in the a + ? condition. High strain rate sensitivity has been observed at 650°C (a + Fe3C), but not reported as such, by Bailey, Dickenson, and pearson14 in 1931 at a strain rate of about 10-9 per min. It then remained to determine whether high tensile elongations would be observed in a rate-controlled test at constant temperature and at what strain rate strain rate sensitivity values greater than 0.5 would be observed. Since previous experience8 had indicated the importance of fine grain size to realizing high m at reasonable strain rates, it was first necessary to produce an ultrafine grain size and then keep the grains from growing during the test. The results of this investigation show that fine grain size can be readily produced16 and maintained by restricting the temperature of testing to below the ? transus. Further, superplasticity (high m and large uniform elongation) is observed. However, the strain rate range is only marginally useful for commercial forming operations with the finest grain size produced. MATERIAL The material investigated initially was a 1.9 wt pct Mn, 0.42 wt pct C, hot-rolled bar previously used by Low and Turka1015 and available in the laboratory. The 0.500-in. round was cold-rolled to a 0.090-in. flat, annealed for 4 hr at 850°C in argon, air-cooled, and cold-finished to 0.050 in. Subsequently, four additional steels of the compositions given in Table I were investigated to explore the effects of manganese, carbon, and test temperature on the observed stress-strain rate behavior. These steels were melted under argon, cast to 0.75 by 2 by 5 in. slabs, hot-rolled at 850°C, surface-finished to 0.13 in., and cold-finished to 0.050 in. Sheet tensile specimens 0.200 in. x thickness with 1- or 2-in. gage length were cut parallel to the rolling direction. Table I also includes the nominal transformation temperatures for the AISI 1340 and the four experimental steels. EXPERIMENTAL PROCEDURE Production of Fine Grain Size. Ultrafine grain size (1 to 5 p) was considered essential for this studv. Grange16 has described two techniques for producing

Jan 1, 1969

H. H. Campbell, Steelton, Pa. (communication to the Secretary) : I wish to thank Mr. Webster for the copious quotations he has made from my writings, as he has given nearly all the arguments I wish to advance. It is necessary to note, however, his statement that most of his experiments were made on universal-mill plates, and that these were not subject to my condemnation of irregularity. I think this is a mistake. It is well known that universal-mill plates are finished under very different conditions of temperature, with the express purpose of regulating the tensile strength. This is a perfectly legitimate practice; but it renders almost worthless any calculations on the relations of the chemical and physical equations when the influence of such finishing is omitted. Another important point Mr. Webster has not answered at all. I have shown by an excerpt from his own table that two entirely different formulæ may be constructed; and it is undeniable that one is as valid as the other, since Mr. Webster started with no premise at all save an assumption that the effect of carbon was constant. This was an assumption pure and simple, and hence has no special virtue. The whole result of Mr. Webster's investigation is not that the effect of carbon is a constant, and that those of phosphorus and manganese are variables. On the contrary, there are two answers, with nothing to show which is right. We learn that if carbon is a constant, then phosphorus and manganese are variables; but that if phosphorus and manganese are constants, then carbon is a variable. This is a distinct advance over complete ignorance, but it is not final and satisfactory from either a mathematical or metallurgical standpoint. Regarding my own formulæ, I would say that they are used regularly in the testing-laboratories of the Pennsylvania Steel Company. The tensile strength of every heat is calculated

Jan 1, 1899

By J. F. Lewis

Believing that one of the essential points in mining, as in all other business, is to know the expense incurred in each particular department, I have carefully kept an account with each department for the past three years; and, as it may be of interest to some of our members, I herewith present it to the Institute, reduced to per centages of the total yearly expense, showing the cost for materials, repairs, expenses, tools, team accounts, powder, oil, and fuel, also for labor under its several heads: 1875—Materials. 1875—Labor, Repairs,...040 Expenses,....016 Team,. .. .. .017 Machinery,. .. .055 Tools,..006 Repairs,. .. .027 Improvements,.....030 Washer,. .. .076 Oil ..008 Pit,.. 178 Powder,..,043 Dirt,.. 130 Fuel,. .325 Superintendence,. ..050 .485 .516 100.1 1876—-Materials. 1876-Labor. Repairs,. . • .. .043 Expenses,......012 Team,.011 Machinery,. .. .090 Tools,..005 Repairs,... 027 Improvements,.....007 Washer,. .. .085 I,. ...,015 Pit,.. 139 Powder,. .. .. .030 Dirt,.. 160 Fuel,...321 Superintendence,. ..078 .444 .559 100.3 1877—Materials. 1877—Labor. Repairs,......102 Expenses,......019 Team,..031 Machinery,. .. .050 Tools,..030 Rrpairs,. .. .046 Improvements,....,031 Washer,. .. .057 I,...009 Pit,.....179 Powder,...035 Dirt,.. 162 Fuel,...200 Superintendence,. ..054 .457 .548 100.5 Average for the three years 1875, '76, and '77. Materials. Labor. Repairs,...062 Expenses,...016 Team,..016 Machinery,. .. .065

Jan 1, 1879