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By E. H. Mohr

At the McGill concentrator of the Nevada Consolidated Copper Co., all flotation operations have been carried out in Forrester cells since November, 1926. In respect to cost of operation, the new cell has proved to be superior to the Callow, which it supplanted, and its incorporation in the flow sheet has resulted in a marked improvement in the metallurgy. Before citing the advantages of the new machine over the old, it should be explained that the Forrester has not only replaced the Callow, but it has made possible the elimination of a number of tables as well. When Callow cells were in use, table concentration preceded flotation. The ball mill pulp was elevated, by means of air lifts, to roughing Wilfley tables situated two floors directly above the flotation floor. On an intermediate floor were additional tables which cleaned the concentrate from those above. The finished table concentrate constituted approximately 60 per cent. of the total mill production, and contained about 40 per cent, of the recovered copper. The table tailings were returned to the classifiers, the overflow from which went to the flotation cells and the oversize to the ball mills. As soon as the Forrester cells were installed, this tabling operation was discontinued. The ball mill pulp now discharges into the classifiers direct, without the intermediate tabling. It was impracticable to ernploy the present flow sheet when Callow cells were in use, for the reason that unless the great,er part of the heavy mineral was first removed, it accumulated on the mats and adversely affected the flotation operation. By tabling ahead of flotation, it was practicable to maintain the concentrator at 10 to 20 per cent. greater capacity (depending up on the pyrite contnt of the ore) than was possible by flotation alone. This was due to the necessity for finer grinding in the latter case. Even though the table conecntrates contained only 6 to 8 per cent'. copper content, the low smelting costs made it advantageous to operate at high mill capacity, at the cost of low grade of product. Standard Section equipment With the old flow sheet, a standard section consisted of four ball mills and classifiers, one air. lift, 20 roughing tables, 10 cleaner tables, 12 primary

Jan 1, 1928

By C. R. Fettke

In 1914, the officials of the Brundred Oil Corpn., faced with the problem of introducing new methods to increase production in the old and nearly depleted pools of Venango County, became interested in the Smith-Dunn (Marietta) process which was at that time being tried out in southeastern Ohio and which was already yielding very encouraging results. A license to use the process in Pennsylvania was secured from the owners of the patents. These patents were later declared invalid. The method was first used in Pennsylvania on a property consisting of about 434 acres, of which 300 are productive, at Hamilton Corners, 15 miles northwest of Oil City, in Cherry Tree and Oakland Townships, Venango County. The producing horizon is the First Sand of the Venango Group. A small oil pool was opened up in this vicinity in 1904. By July, 1916, when the compressed air was first introduced to restore pressure, the production had dropped to a point where it was no longer possible to continue profitable operation. From that time until March, 1927, over 100,000 bbl. of oil have been recovered from the tract. The property is being operated at present by the Brundred Oil Corpn. and LUX. The 1926 production, amounting to 10,650 bbl., was only 400 bbl. short of the maximum reached during any year of the 10-year period that the process has been in operation. Inasmuch as the Hamilton Corners pool is the first one in Pennsylvania in which the Marietta process was tried out, and the one in which it has been longest in continuous operation, considerable interest attaches to the results obtained. Through the courtesy of H. D. Brown and W. J. Brundred, officials of the Brundred Oil Corpn., all their data on this operation were made available to the writer in connection with an investigation of rejuvenation methods in the State for the Pennsylvania Geological Survey. Stratigraphic Position of the Producing Sand The producing sand at Hamilton Corners is encountered at depths of from 364 to 560 ft., depending on the location of the well and the topog-

Jan 1, 1928

By R. Van A. Mills

Crude oils are capable of dissolving quantities of gas under pressure. This fact has been known for some time, but questions have arisen as to the effects of gas in solution upon the characteristics of the oil. Previous investigations4 show that gas in solution in an oil affects the viscosity and surface tension of the oil, but the effect's on the volume and A. P. I. gravity of the oil have not been known. The results given in this report show that there is a decided change both in volume and in the A. P. I. gravity of the oil due to the solution of the gas in the oil under pressure. As gas is dissolved, the volume of the oil and the A. P. I. gravity increase. The converse of this phenomenon is also true: if the gas is released from a saturated oil, there is a shrinkage in volume and a decrease in A.P.I. gravity due to the release of gas from solution. However, various oils show marked tendencies to retain a portion of the dissolved gas upon releasing the pressure to that of the atmosphere. This retained gas has an appreciable effect on the volume and A. P. I. gravity of the oil because the oil does not resume its initial volume or gravity while it retains dissolved gas. In a sense the oil has been "Freshened" and will not return to its original or weathered volume until it loses some of the lighter fractions. Wiggins5 has shown that a fresh oil decreases both in volume and in gravity because of the weathering of the lighter fractions while the oil is standing in storage tanks.

Jan 1, 1928

By S. J. Cook

Copper, a world commodity, and the first metal used by man, played a great part in the beginnings of modern civilization, which rests so dependently on the utilization of metals. Then, long after the close of the so-called 'bronze age,' when iron and steel had attained great prominence as the world's most important metals, the practical application of electricity to industry and commerce, for the improvement of every phase of man's multitudinous activities, gave a new impetus to the production of copper. Improved metallurgical practice made it possible to work low-grade properties at a profit. Research disclosed many new uses for copper. The metal, now produced from the mines of the world in the proportion of about one pound to every 50 tons of pig iron, has attained an importance which rivals that of iron and steel in the commerce and daily life of every nation. New fields of copper-bearing ore have been discovered in Canada in recent years. Established mines in the United States and Chile are producing on a great scale. Africa looms up as one of the great question marks in the future of copper. Whereas, a few years ago, the end of the world?s resources was predicted as being in sight, the evidence now available seems to show that the copper production of the world is likely not only to continue, but to increase for a long time yet to come. Canada's future in copper is a great subject; in the present paper only a few of the most outstanding factors affecting Canada's destiny in this large field may be noted, but if consideration of the points raised herein serves to focus attention on the magnificent possibilities of Canada as a producer of copper, the preparation of the paper will be more than justified.

Jan 1, 1928

By Ralph Arnold

Since 1915, when Elk Basin field was brought in, eight oil fields have been developed in Montana and the production has arisen from 50,000 bbl. in 1916 to 8,000,000 bbl. in 1926. The production for 1927 was 5,121,600 bbl. and the total up to the end of 1927 was 27,138,239 barrels. The eight fields, with their year of discovery are: Elk Basin, Carbon County (1915); Devil's Basin, Petroleum County (1919); Cat Creek, Petroleum County (1920); Soap Creek, Big Horn County (1921); Kevin-Sunburst, Toole County (1922); Lake Basin, Stillwater County (1924); Pondera, Pondera and Teton counties (1927); and Bannatyne, Pondera and Teton counties (1927). About 170 wildcat wells have been drilled in the state of which 8 were successful and 162 gas wells or dry. Hence, only one out of 21, or 5 per cent. of the wildcats have been successful. The average depth of the wells has been 1600 ft. and the average cost $32,000 apiece. • Up to Jan. 1, 1927, a total of 1376 wells have been drilled in the producing oil and gas fields of the state, of which 904, or 66 per cent., were successful oil wells; 82, or 6 per cent. were gas; and 390, or 28 per cent, were dry. The percentage of dry wells is excessive as compared to the wells in other states, due to the uncertainties of limestone reservoir rocks. The total production of oil to Jan. 1, 1927, has been 22,016,639 bbl. and of gas 7,265,330,000 cu. ft. The average price at the well for the oil has been $1.47 per bbl. and for gas about 4 c. per 1000 cu. ft. The value at the point of consumption has been about 23 c. per 1000 cu. ft. The total revenue derived from crude oil has been $32,277,119, and from gas 8350,613, or a total income to the producer of $32,727,832. Each well drilled in the state has already (to Jan. 1, 1927) averaged a return of over $21,000. The total number of domestic (Montana) oil and gas companies organized, since the first in 1885, has been 844, of which 702 are still alive and 142 dead. Oil and gas companies registered for operation within the state to Jan. 1, 1927, but with outside charters, are 143, of which 66 are alive and 77 are dead. Outside the few distributing companies, which are included in these figures, the grand total of 997 companies which have

Jan 1, 1928

By Wm. W. Adell

"These hydrocarbons belonging to the same chemical series as methane, having the general formula CnH2n have many chemical properties in common with methane and their addition to a lean gas charges the properties and burning characteristics of the gas in the same general direction although to a different extent. The hydrocarbons of this series do not readily enter into chemical reaction with other substances and therefore are incapable of combining with oxygen or polymerizing in the disturbing system and thus cannot cause gum and room troubles commonly met with in the distribution of manufactured gas.As the number of carbon atoms in the molecule increases, i.e. in proceeding from methane throughout the series, the oxygen requirements for the complete combustion of unit volume of the gases also increases; in other words, the calorific values of these hydrocarbons (as gases) increases from methane. Similarly the specific gravity increases from methane in the same order. In Table 1 are shown some of the physical constants and properties of a few of these hydrocarbons which hive bearing on their use for enriching gas."

Nov 1, 1927

By E. H. Denny

"IntroductionOn May 27, 1927, a coal-dust explosion occurred at the Palagua No. 5 mine of the Victor American Fuel Company, Delagua, Colorado, resulting in the loss of even lives and in and in considerable damage to the main slope and to several overcasts the explosion did not extend into the mine working where 125 additional men were employed but escaped uninjured. It is believed that the saving of these 125 men and the evidence of large property loss were due in a large measure to coal-dusting and of other sanity measures taken by the coal company management. A number of features connected with the explosion and mine safety practice seem worth the attention of the mining public and grateful acknowledgment is made to the Victor American Fuel Company for its aid in assembling the data herein contained."

Nov 1, 1927

By K. B. Nowels

"INTRODUCTION For the last several years the oil industry has been turning more and more toward conservation arid the study of related production problems. It is generally conceded that ultimate recovery is increased by holding the natural gas in thy sand which is net needed in lifting the oil. The retained gas lowers the viscosity and surface tension of the oil and helps flow the oil from the sand. Lewis states that ""while the operator can not control the original conditions of energy and resistance in the sand, he can partly control the efficiency of expulsion. As it is the energy contained in the compressed and absorbed gas rather than the oil that is exhausted, it is but logical to judge the efficiency of a producing method largely by the relative quantities of gas produced with each barrel of oil. If by a change in method the producer lessons the proportion of gas with each barrel of oil, he should increase the total recovery- of oil correspondingly, even if the rate of production is temporarily reduced somewhat.""The effect of ""pinching in"" or controlling the flow of oil wells in an effort to lessen the proportion of has never been definitely known. The general belief has been that ""pinching"" a flowing well causes the oil and gas volumes to be reduced proportionately, maintaining the same gas-oil ratio as before the reduction in flow was made. Studies of gas-oil ratios in many fields have shown that much gas has been wasted, insofar as its effectiveness in oil production is concerned. Swigart and Bopp carried."

Oct 1, 1927

By C. H. Herty, J. K. Gaines

"Nearly every piece of electrical equipment used in mines ""breathes."" In other words, motors, controllers, rheostats, switches, and other similar equipment, even though encased in seemingly tight compartments, breathe in the atmosphere that surrounds them.As the apparatus is used, the temperature of metallic parts is changed generally in positive direction through the heat by friction and the heat due to the electric current. When the apparatus is idle it gradually cools down to the temperature of the surrounding atmosphere.This increase of temperature during operation and return to normal temperature when operation stops alternately raises and lowers the temperature of the atmosphere within the compartments which, in strict accordance with Charles' law -T = VT1 V'will expand or contract in proportion to any given temperature change.As compartments are not gas-tight, such expansion and contraction will force the atmosphere out of the compartment =on expansion and suck the surround¬ing atmosphere into the compartment during contraction, hence the term ""breathing.""Investigators of explosion-proof equipment have recognized that such an interchange would take place and have designed their equipment to safeguard possible explosions within the compartments."

Jul 1, 1927

By Thomas Varley

"The literature on flotation of oxidized ores except for patents (especially for reagents) is very sparse. The Bureau of Mines in 1936, published a circular on the subject, by Ralston and Allen. The treatment of oxides by flotation was then in its infancy, but several of the most important mining companies in the Western United States and Mexico are now operating flotation plants for treating oxidized ores. The purpose of this present circular is to review the progress made and bring the subject up to date. One of the writers of the 1916 report (Mr. Allen) has been associated with some of the most important mining companies who have put into practical operation the process of flotation of oxidized ores; among these companies are the Shhttuck Arizona Copper Co., Bisbee, Arizona (now the Shattuck Denn Co.) and the San Francisco Mines of Mexico, Ltd., San Francisco Del Oro, Chihuahua, Mexico. His experience and other sources of information have been freely drawn on in pre-paring this paper. Mr. Ralston, assistant chief metallurgist of the Bureau of Mines, contributed many valuable suggestions and criticisms.Sulphidizing Reagents for Oxidize Ores.The various reagents and methods that might possibly be used for sulphidizing were summarized by Ralston and Allen as follows:""Sulphidizing (1) by the use of hydrogen sulphide on either the dry or the wet crushed ore, (2) by the use of solutions of the various sulphides and sulpho-compounds of sodium, (3) by the use of solutions of the various sulphides and sulpho-compounds of calcium, (4) by the use of sulphur vapor, (5) by the use of a sulphureted oil, (6) with colloidal sulphur."

Jun 1, 1927

By George S. Rice

"""To prevent the propagation of mine explosions, the Bureau of Mines, Department of Commerce, recommends rock-dusting all coal mines, except anthracite mines, in every part, whether in damp or dry condition. It also recom¬mends that rock-dust barriers be used to sectionalize the mine as additional defense; but these should not be regarded as a substitute for generalized rock-dusting."" (Mine safety decision, No. 5, April 7, 1927.)The purposes of this circular are to present concisely the requirements for effective rock-dusting of coal mines in order to prevent propagation of mine explosions, and to point out the principal related facts on explosibility of coal dusts and mixed coal-mine dusts, as determined by extensive testing in the Experimental Mine of the Bureau of Mines. study of these principal facts on coal-dust explosibility in conjunction with the recommendations for rock-dusting, should help to make clear to mine operators and others concerned the necessity for systematic rock-dusting in all coal mines except anthracite mines, and the futility of inadequate or sporadic rock dusting.The descriptions of nearly 1000 explosion tests in the Experimental Mine are available in a forth-coming bulletin2 and in earlier publications.3For detailed specifications as to the kind of rock-dust, amount to use, where to be applied, and method of sampling and testing, the reader is referred to Bureau of Mines Serial 26064, and American Engineering Standard Committee ""Recommended American Practice for Rock-Dusting Coal Mines"" quoted in Bureau of Mines Information Circular No. 60305.Summary of Specifications for Rock-Dusting1. Mines to be rock-dustedAll coal mines, except anthracite mines, should be rock-dusted.2. Extent of rock-dustingAll open accessible parts of a coal mine should be rock-dusted, including slopes, entries, cross,-cuts, and rooms, headings and pillar workings to within at least 50 feet of the face.3 Amount of rock-dustingAfter cleaning up the coal dust as thoroughly as practicable, sufficient rock-dust should be used to have the mixture of remaining coal-dust plus the rock-dust in any zone contain 65 per cent or more of inert or noncombustible matter. First dusting may require 3 pounds to 5 pounds per linear foot of passageway.4. When to rock-dust In any zone or section (made by dividing the mine for rock-dusting purposes) when the incombustible content falls to 55 per cent, that section should be re-rock-dusted so as to bring the incombustible content well above 65 per cent."

Jun 1, 1927

By L. C. IlsLey

"Nearly every piece of electrical equipment used in mines ""breathes."" In other words, motors, controllers, rheostats, switches, and other similar equipment, even though encased in seemingly tight compartments, breathe in the atmosphere that surrounds them.As the apparatus is used, the temperature of metallic parts is changed generally in positive direction through the heat by friction and the heat due to the electric current. When the apparatus is idle it gradually cools down to the temperature of the surrounding atmosphere.This increase of temperature during operation and return to normal temperature when operation stops alternately raises and lowers the temperature of the atmosphere within the compartments which, in strict accordance with Charles' law -will expand or contract in proportion to any given temperature change.As compartments are not gas-tight, such expansion and contraction will force the atmosphere out of the compartment =on expansion and suck the surround¬ing atmosphere into the compartment during contraction, hence the term ""breathing.""Investigators2 of explosion-proof equipment have recognized that such an interchange would take place and have designed their equipment to safeguard possible explosions within the compartments."

Jun 1, 1927

By Alden H. Emery, J. J. Forbes

"IntroductionThe data contained in this paper were collected during the course of an investigation which covered 15 representative coal mines in 6 coal-mining States. The purpose of the investigation was to determine by atmospheric sampling how much dust was raised into the air during the various operations of coal mining, such as undercutting with machines, loading coal by hand, and transporting it from the working face to the surface. The data thus obtained were considered from two angles - namely, the possible physiological effect of inhalation and the explosion hazard of the dust. No attempt will be mode to discuss the former factor in this paper.CONDITIONS OF MININGThe mines in which this investigation was conducted were considered representative, and it is believed that the results obtained will suffice for the average dustiness encountered in most coal mines. .All of the coal mined was bituminous, from beds 30 to 120 inches thick. Only the ordinary room-and-pillar system of mining was employed. Daily production ranged from approximately 700 to 1500 tons and the men employed from 150 to 450. Coal was undercut by short-wall mining machines in all mines, with the exception of one in which pick mining was employed. Loading at the face was done by miners; none of the mines used mechanical loaders. Electric drills, both for brushing roof and for shooting coal, were commonly used although some roof work was done with jack-hammers and a. little of both with augers. Coal was hauled by motor, mule, or rope power in end-gate cars with capacities ranging from 1600 to 3600 pounds. With few exceptions, coal was won at the face by dry methods - that is to say, no water was employed fox wetting down the dust either during undercutting, loading, or transportation."

Feb 1, 1927

NOT all the lead in the country comes from the big operations. A member sends in this photograph of the wash-up from the "Old Timers Lead Mine," at Galena, Ill. He omitted to inclose a flow-sheet of the concentration process, which detracts somewhat from its value to the technical man, and cost figures are lacking. Perhaps he was run off the lease when his questions on milling recoveries became too searching. Still and all, according to the picture the plant ap-pears to be operating efficiently. It is reasonable to believe that the cost of electric power per ton milled is held to a low figure. We commend the proper pro-fessional stance of the gentleman on the business end of the hand jig, though we look in vain for the time honored spring board to aid him in giving the most efficient stroke.

Jan 12, 1927

By Clarence Claghorn

ONE of the simplest and most easily effected steps toward mechanization and concentrated mining in coal mines is the substitution of transport or room conveyors for the customary tracks in rooms, thus bringing the coal to the cars instead of taking the cars to the coal. As this involves little or no change in the established room and pillar layout, it appeals to the conservative operator who is more or less fearful of changes in system involving the element of roof con-trol. An increasing number of these room conveyors would seem to attest the favorable commercial results secured. Rooms are naturally driven as wide as roof conditions permit, providing maximum tonnage from each room cut. If the rooms are more than 12 to 14 ft. in width the room conveyor is usually set along one rib, a porta-ble face conveyor being set along the face itself and within easy shoveling distance of it, so arranged as to discharge to the transport conveyor. As the room ad-vances the latter is lengthened and the face conveyor moved up laterally. The advantages of this layout are, briefly, low lifts, no shoveling, no waiting for cars. It gives easy shovel-ing conditions and continuous production so long as there is loose coal at the face. Several loaders are usually employed at the face and the room is loaded out several times each shift. In fact, where the rooms are fairly wide, by judicious management, cutting and load-ing may go on simultaneously. Under these conditions, naturally, the face conveyor plays an important part as it is the appliance on which the coal is actually loaded. Someone has aptly stated that the loading is a question of "foot pounds," which is an appealing way to put it, for it is the number of pounds to be moved by the number of feet which measures the work to be done. It can easily be seen that the design of the face con-veyor is a matter of importance. It might be an im-perfect target for the shovel or of an awkward shape and height, and so involve extra effort on the part of the loader, tiring him when kept up continuously and at the same time slowing up his shoveling speed.

Jan 12, 1927

By F. A. Orth

COAL-mine opera- tors face a difficul- ty in notifying men when there is no work. If the miners come to the shaft when there is no work, they must be paid, by agreement, two hours' wages. This involves a considerable loss since it is not uncommon to em- ploy two or three hun- dred men or more at a single shaft. Many mines have solved the problem by using an electric siren. This carries the "no work" message to all of the miners within a ra- dius of from one and one- half to two miles, so they do not trudge uselessly to work and the operator saves the two-hours wage payment. At the Valley Smokeless Coal Co., Johns- town, Pa., such a siren serves as a start and quit- work signal for three mines which previously re¬ quired three individual signal systems. Similar units are used by the Old Ben Coal Corp. mines, Dolly's Smokeless Coal Co., Rhonda Coal Co., Bird Coal Co., and hundreds of others. Many other applications of the electric siren have been found in mines. They are used on underground locomotives, to awaken miners in the morning, to tell them it is time to come to work, to sound the start and quit-work signal, and to warn of fire or accident. The sirens are most generally used to give a start and quit-work signal, fire, and general emergency alarms as well as no-work signals. They require 3 and 5 hp. to operate. The smaller unit has a sound radius of from three-quarters to one mile, while the larger siren can be heard over a distance of from one and one-half to two miles. The 5-hp. unit has been heard for as great a distance as 14 miles, and 10 miles is not at all uncommon. One of the outstanding features of the 3 and 5-hp. units, which is uncommon in the smaller sirens is that they may be adapted to sound code signals. When used to sound a fire or general emergency alarm the siren may tell at the same time where the fire or acci-dent is. When a remote control device is used with a siren it is possible to operate the siren from any number of distant points. Any number of "start" buttons may be placed at various places. By using one "start and stop" button where the remote control is mounted, and one or more "start" buttons at various places about the plant, it is necessary to run only two wires to the various "start" buttons. If "start" and "stop" buttons are used altogether, then three wires must be run.

Jan 11, 1927

By Charles Hawes

WHEN sulfur is encountered in objectionable amounts, it is regarded as the most trouble-some element for the mine operator to control. It exists in two conditions in iron ores, as sulfide in iron pyrites and as sulfate in gypsum and barite. The sulfate radical (SO,) may also be linked to one or more of the several other elements found in the iron ore compound. The only dependable method for the de-termination of sulfur, particularly when found in the insoluble residue, has been the so-called fusion method. This is a long and tedious process involving several hours for its completion. In looking for a more rapid method which would be .applicable to all iron ores, the writer investigated the work of M. Groger1 who in 1881 showed that by heating pyrite with iron out of contact with air, the pyrite is reduced to iron sulfide and from the latter all of the sulfur will be given off as hydrogen sulfide gas on treat-ment with hydrochloric acid. FeS2 + Fe = 2 FeS FeS + 2 HCl = FeC12 + H2S In 1891 F. P. Treadwell2 not only confirmed the results of M. Groger but also found that iron powder would reduce to sulfide the sulfate radical of any substance, including barite, if not found in excessive quantities. The writer found this to be true and developed a method, in cooperation with F. J. Baker, chief chemist, mining department, of the Cleveland-Cliffs Iron Co., Ishpeming, Mich., for the determination of sulfur in iron ores which is not only very rapid but also accurate. Pure iron ore powder, reduced by hydrogen, gave good results but was found to be very slow in reacting. A high silicon iron with a low sulfur content of 0.012 per cent was found to be. much more active than the pure iron and gave excellent results.

Jan 11, 1927

By E. Seidl

THE basic material for testing aluminum, copper and zinc is a cast metal, principally in the form of wire bars (Figs. 1 to 3) and plates for the produc- tion of sheets or strips, (Figs. 4 to 7). Experience has proved that the chemical and crystallographic proper-ties of such cast metal exercise a certain influence when it is being worked, which is usually done while the metal is hot. In a chemical sense the slight impurities, which even the purest industrial metal contains, have a disturbing effect. They settle either along the outside limits of granulation, as in the case of aluminum and copper, or else in the interior of the crystal, as in the case of zinc; but frequently are also found accumulating at certain points (formation of the blowholes and skin) (Fig. 7). The crystallographic character of the metals is either that of uniformly fine granulation, or else there occurs a certain distinct casting texture marked by sharply defined cooling conditions and consisting of crys-tals of a pronounced stalk-like or blade form. Since we generally distinguish between a crystal texture and a crystal structure, the term crystal texture is used here for the arrangement of the crystals relative to each other and their microscopic composition; crystallic structure is used to mean the radioscopically ascertain-able structure of the crystal. The influence of the impurities and of the crystalline character on the working of the metals has been fre-quently pointed out in practice as well as in science.

Jan 11, 1927

By Olav Dalen

A HUNDRED years have passed since Wöhler made the first few particles of aluminum by decompos-ing aluminum chloride with potassium. In 1854 Deville used sodium to decompose the double chloride of aluminum and sodium, but even various subsequent improvements of the process, especially by Castner, did not sufficiently decrease the cost of the metal to bring it into general use. In 1862 Monckton proposed to reduce Al O? with carbon by the aid of the electric current, but the efforts of the Cowles brothers to do so were not successful and in 1884 they turned to making aluminum alloys by electrolysis. At about the same time Hall in America and Heroult in France success-fully worked out the technology of dissolving A12O3 in fused cryolite and electrolyzing the bath. It is hard to realize that forty years ago the annual production of aluminum was only 30 to 40 tons per year and the price of the metal thirty times what it is today. Great strides in decreasing the cost of production, improving the quality of the metal, and increasing the output have been made in the lifetime of middle-aged men. The large consumption of electrical energy in the form of direct current makes it necessary to locate aluminum-producing plants near waterfalls, to avoid transmission losses. Norway with its abundant water-falls is therefore a logical place for the development of aluminum production, even though it is necessary to import the bauxite, which is the raw material of the process. It was foreigners who first started the aluminum in-dustry of Norway and the first two plants were built by the British Aluminium Co. in 1906 to 1908; one at Vigeland near Kristiansand, and the other at Stavan-gerfjord in Nordfjord. These two plants are still oper-ating and producing over 3000 tons a year. When the plant at Vigeland is enlarged the production of the company will be more than 4000 tons a year.

Jan 11, 1927

WHEN one leaves the busy street and enters a library, the closing of the door behind him marks his passage into another world. Outside is the world of phenomena and appearances-of thronging pedestrians bustling about their business, of gregarious sights and sounds, of insistent auto-mobiles. Inside, on dusty shelves, is the stored learning of civilized man-the recorded ideas of countless generations. It is somewhat of a magic world. Here are the theories and secrets for which thousands of men toiled and gave their heart's blood. To produce one book on one phase of an ob-scure-subject may have required the best efforts of a group of men unique in their period. To prove one theory, or es-tablish a single application of a theory, may have taken the devotion of a genius who sacrificed his life to his work. This theory is perhaps stated in one paragraph of unassum-ing type, and the library contains millions of such para-

Jan 11, 1927