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J. E. Johnson, Jr., Glen Wilton, Va. (communication to the Secretary*):—Mr. Meissner announces early in his paper that one of its purposes is the discussion of my paper entitled, Notes on the Physical Action of the Blast-Furnace,' with which he disagrees in part; and as the second stage of the discussion of this important subject has centered around his paper, some reply by me may not be amiss. Unfortunately, Mr. Meissner has not indicated a single statement or conclusion in my paper that he wishes to controvert; but as there is evidently a difference of opinion between us I will disregard this fact, and will discuss those conclusions of his that seem to me not to be justified by the facts of general practice, or even by the data which he produces to support them. Let me say, however, that I am a believer in the dry-air

Jan 1, 1908

Albert Ladd Colby, New York, N. Y. (communication to the Secretary†):—I observed (Trans., xxxvii., 585) that to obtain tenders from several American mills, the foreign engineer should modify his maximum phosphorus to 0.10 per cent., not as Mr. E. Windsor Richards quotes me, that no American rail-maker can produce rails under 0.10 per cent. of phosphorus. Mr. Richards claims that no English engineer would agree to accept 0.10 per cent. of phosphorus on any terms whatever. Mr. Webster writes that only after an engineer has .been convinced that rails can be made in America equal in every respect to those he is getting abroad, should he be asked to modify ally conditions in his specifications. I know it to be a fact that during recent years in many cases, as, for instance, When delivery could be secured more promptly in the United States than in Europe, the consulting engineers of several British and colonial railroads have frequently agreed to modify their phosphorus requirement to a maximum of 0.10 per cent., and the rails delivered' under these modified specifications have, under like conditions, given just as satisfactory service and proved to be no more brittle than similar sections of 0.07 per cent. phosphorus rails, rolled in England under the same specification except without modification as to phosphorus. Furthermore, it would appear from the analyses of British rails, quoted by E. A. Dancaster,2 in his discussion of Mr.

Jan 1, 1908

By W. S. Ayres

I. Introduction. This cavern was discovered Oct. 32,1904, by Mr. Charles 8. Deutschman, in company with whom I made, May 29 to June 3,1905, at the request of Mr. Howard Douglas, Superintendent of the Canadian National Parks, the first exploration of it for the Canadian government. The results were stated in a paper, orally presented, with lantern-views from my photographs, at the British Columbia Meeting of the Institute, Victoria, B. C., July 5, 1905.* The present paper embodies also the results of a second examination, made Oct. 25 to 29, 1905. The accompanging map, Fig. 1, will serve as a guide to the following description. 11. Location. The cavern is situated at snow-line, at the head-waters of Cougar creek, on the west slopes of the Selkirks, about 2 miles north from Ross Peak water-tank, and 5.5 miles west from Glacier station, on the main line of the Canadian Pacific Railway. It was then reached by an arduous climb from the water-tank, up the ravine of Cougar creek, for 8,000 ft. (2,000 ft. of altitude) over rock- and snow-slides, and through a thick tangle of alders. But an easy and very picturesque trail has, during the past summer, been opened by the government from Glacier station, which is also a hotel of the railway company. Figs. 3, 3 and 4 represent views, not heretofore published, of the grand scenery of this region, so rapidly becoming the object of attraction to thousands of tourists from all parts of the world. These views, as well as those shown in Figs. 5, 6, 7, 8

Jan 1, 1908

By George A. Packard

THE experiments here described were made under my supervision while temporarily acting as head of the Department of Metallurgy at the Missouri School of Mines, at Rolla. The work was done by Messrs. W. E. Brown, W. C. Richards, and F. L. L. Wilson, and the description of the results forms a portion of a thesis presented for the degree of Bachelor of Science. These results are submitted because I have seen no description of the application of pot roasting to the treatment of a copper-concentrate. This work followed that already described in the discussion of the ' Lime-Roasting of a Galena-Concentrate,"' and was similarly occasioned by the lack of a furnace of the reverberatory type in which the copper-concentrates could be smelted. The material for the tests was a mixture of three lots available. The first consisted of 8-mm. jig-concentrates and the second of 0.5 mm. table-concentrates, from the San Juan district, Colo. Both contained pyrite, chalcopyrite and galena. The third was a lot of copper-ore, found in the laboratory, which had been crushed through 8-mm. screen, and had at some previous time, before the laboratory roasting-furnace was torn down, received a partial roasting. The analyses of these ores are given in Table I. In order to determine the applicability of pot-roasting as to each lot of ore, and the effect of varying proportions of lime, six preliminary tests were made in a " size N " Battersea crucible, 9 in. high by 6 in. in diameter at top, with a 5/8 in. hole bored through the bottom. The crucible was set in the upturned elbow of a 2-in. pipe, the joint being luted with clay; and air was obtained from a receiver supplied by a compressor. The

Jan 1, 1908

By W. F. Wheeler

IN the study of the coals of Illinois now being carried on by the State Geological Survey, an attempt is being made to determine the most satisfactory basis of comparison between different coals. The following discussion is based upon work done for the survey in the laboratories of the State University and under the general direction of Prof. S. W. Parr. " Pure coal " has been defined by Mr. A. Bement1 as ash- and moisture-free coal, and the use of this " pure coal " as a basis for comparing different bituminous coals has lately been much discussed among engineers in the middle West. By some the B.t.u. of the pure coal is being used to check calorimetric results, and to calculate the calorific value of different coal-samples from the same seam, for which purposes it is necessary to assume-first, that the composition and calorific value of pure coal from different parts of the same coal-seam are uniform, and, second, that these values remain constant after the coal is mined, both of which assumptions there are reasons to believe are inconsistent with the facts. Certain variables are included in pure coal, as ordinarily defined, and disregard of them may lead to serious error. In any event, where delicate shades of difference are involved, no sure interpretation of results can be made, unless these variables be eliminated. As a basis of comparison between coals, ash- and moisture-free coal is much to be preferred to " dry coal," and still more is it to be preferred to " moist coal," as ordinarily reported in analyses. There are, however, two constituents other than ash and moisture which are similar in effect to them, and which

Jan 1, 1908

George A. Packard, Boston, Mass. (communication to the Secretary†):—The very interesting results obtained by Prof. Hofman and his assistants came to my attention when I had temporarily assumed charge of the metallurgical department of the Missouri School of Mines, and had found it, pending the completion of a new building, lacking a furnace in which to roast ore preparatory to the customary lead blast-furnace run. An attempt at lime-roasting had been already determined upon, but the use of a charge which would make a slag of definite composition was a new idea. The results following were obtained by Messrs. Aubrey Fellows, J. C. Long, E. R. Wash, and Dr. T. C. Tseung, under my supervision. It is regretted that the data are not more complete; but the work was done simply incidentally to securing the desired ore for the blast-

Jan 1, 1908

Jan 1, 1908

Prof. Henry M. Howe, New York, N. Y. (communication to the Secretary*):—The results presented in Mr. Mathewson's paper are of very great interest. Perhaps the most interesting is that shown in Table I. and Fig. 1, in which the arsenic decreases in 10 min. from 0.22 to 0.07 per cent. This is such a large decrease that it is to be hoped that Mr. Mathewson will verify it by repeating his tests with a matte of similar composition. This is particularly to be desired, because the simultaneous removal of sulphur appears to be very small. All three blows further agree in showing that the removal of arsenic is in the very early part of the blow. The fact that the removal of arsenic then ceases abruptly cannot be explained completely by the fact that the arsenic has fallen so low as by its lowness to resist further removal, because in the first blow the arsenic becomes stationary at 0.06 per cent., whereas in the third blow it does not become stationary until it has fallen to 0.034 per cent. The abrupt ending of the removal of arsenic is more likely to find its explanation in the composition of the slag, and it is to be hoped that Mr. Mathewson will supplement these extremely valuable data with others in which the composition of the slag at the same time shall be given. The sudden rise of arsenic toward the end of the third blow I suppose must be referred to an error in sampling or analysis.

Jan 1, 1908

Secretary's Note.—M. Beutter's introductory remarks, being simply a resume of Prof. Hone's paper, with a disclaimer of the intention to criticise it, have been omitted, and the remainder of this contribution lias been somewhat condensed, without omitting any essential statements. M. Beutter, St. Etienne, France* (communication to the Secretary†):—Professor Home observes in $ 47 of his paper that the fluid-compression of steel diminishes piping by forcing the liquid and viscous metal, while the pipe is forming, or after it has formed, into the space so produced, and proceeds to study the different systems of compression, alluding to the four principal ones: Whitworth, Illingmorth, Williams, and Harmet. Having now for many years had in use the last-named process, that of M. Henri Harmet, I shall attempt to explain the difference between it and the three other processes named. The Harmet process does not diminish or close the pipe after it has formed, but prevents it from forming; and I may add that it is the only one of the four which produces this result. It is true that the Whitworth process diminishes the interior hollow by localizing it around the central axis of the ingot, which is afterwards removed by trepanning the hollow forg-ings for which this process has been, I believe, always exclusively used. The Illingworth and Williams processes, which, in my opinion, are applicable only to small ingots, of necessity allow the pipe to form, or (to use the expression of Professor Howe) they allow the surface of the lake of liquid steel to sink into the interior of the ingot, since they involve waiting a certain time before compression, so that (in the case of the Williams process) the ingot-mold can be opened without danger, or (in the case of the Illingworth process) so as to avoid the risk that the steel may enter the grooves produced by the removal of the distance-bars. During the time required for

Jan 1, 1908

By A. L. Sweetser

EXPERIENCE has shown how difficult it is to obtain information regarding laboratory-tests in connection with the chlorination-process for the extraction of gold from its ores, and I therefore present the following method, somewhat in detail, for the benefit of those who may desire to pursue research work in this field. The ore chosen was a partly-decomposed porphyry, extremely siliceous and comparatively soft, and of an average value per ton of from $25 to $26 in gold and $0.68 in silver. The chemical analysis gave : Fe2O3, 3.35; FeS, 1.5; MnO2, 0.75; ZnCO3, 4; Al2O3, 3.20; H2O, 0.7; SiO2 and insol., 83.50 per cent. The ore, first crushed to pass a 5-mesh screen, was coned and quartered until a 45-lb. sample was obtained. Samples for assay and analysis, taken from this lot by means of riffles, were crushed to pass a 100-mesh screen. The original sample was divided into 10-lb. lots, of which one was crushed to pass a 10-mesh screen; another through a 12-; the third through a 20-, .and the last through a 30-mesh screen. Because of the production of an excessive quantity of fine material it was deemed inexpedient to crush finer than 30-mesh size-a decision the wisdom of which is proved by the data in Table I., showing the increasing ratio of slimes, in proportion as the ore is crushed finer. In order to determine the percentage of fines in the sizes of mesh selected, a weighed sample of ore was taken from each mesh, and a sample from the 10-mesh lot was passed successively through 20-, 40- and 100-mesh screens, and the percentage remaining on each screen determined. This process was repeated with the 12-, 20- and 30-mesh lots, with the results given in Table I.

Sep 1, 1907

By Richard W. Lodge

Ix the crucible-method of assaying ores for silver a certain amount of litharge is essential to supply sufficient lead to collect the precious metals. The object of this paper is to point out that the use of a .large excess of litharge in the assay of some ores will give results for silver that are uneven as well as low. So far as I know, however, an excess of litharge does not affect the results obtained in the crucible-assay of ores for gold. The main reasons for using, in the crucible-assay, much more litharge than is required to give the necessary lead button are : 1, its action as a flux; 2, its action as a desulphurizer; and 3, its action as an oxidizer, especially on metals like copper and nickel, whereby they are forced into the slag as oxides and thus prevented from passing into the lead button. Hence, by the use of much litharge in the crucible-assay more-ore can often be taken than in the scorification-process, and a lead button obtained which can possibly be cupelled at once or after a single scorification. The method is specially advantageous with an ore carrying much copper or similar impurity and poor in silver, when the assayer does not wish to resort to a wet-analysis for the determination of the silver. It is well known that some ores give better results when assayed by the scorification-method, while others give better results by the crucible-method. For several years I have noticed that, when much litharge was used with certain sulphide and arsenical ores, the results were considerably lower than when the scorification-method was used. This fact was more forcibly brought out in connection with certain work carried on this year by Messrs. H. A. Frame and

Sep 1, 1907

By Thomas Leonard Watson

SULPHIDE ore-bodies of more or less lenticular shape occurring in metamorphic crystalline schists, gneisses, and. slates, and conforming closely in strike and usually in dip to the inclosing rock, have been recognized and described along the, Atlantic seaboard from Quebec to Alabama. The ore-bodies do not entirely conform, in all cases, to the structure of the inclosing schists, but they sometimes cut across the foliation in dip, though conforming more closely with the direction of strike. In composition the principal sulphide mineral is usually pyrite or pyrrhotite; or both, accompanied by copper, frequently gold, and almost always some sphalerite and galenite. Other. metallic ores are, so far as these sulphide bodies have been investigated, less common; silver is not uncommon, and in some of the pyrrhotite masses nickel is present in quantity sufficient to be commercially valuable. Cobalt frequently accompanies .the nickel, usually in smaller amount, and the two vary much in relative proportion. Quartz and calcite are probably the most common of the, non-metallic minerals. A number of silicate minerals are frequent representatives in one place or another; garnet, amphibole, biotite, pyroxene, zoisite and others. The sulphide bodies of Virginia, comprising both pyrite and pyrrhotite, are among the most extensive along the Atlantic seaboard. Among the pyrite bodies may be mentioned the well-known and extensively worked mines of Louisa and Prince William, counties, located on' the main pyrite belt (A, Fig. 1) of the middle and northern, eastern Piedmont region in Virginia, and among the pyrrhotite bodies is the famous " Great Gossan Lead "(B, Fig. 1) of the Floyd-Carroll-Graysou coun-

Sep 1, 1907

By Edward W. Parker

(Toronto Meeting, July, 1907.) NOTE.-The material from which this paper has been prepared was collected for the U. S. Geological Survey Bulletin, Contributions to Economic Geology, 1906, and appears also, though in somewhat more extended form without illustrations, in that publication. ALTHOUGH the briquetting of coals and lignites has been carried on for many years in Europe, and has reached a particularly high state of development in France, Belgium, and Germany, it has made comparatively little progress in the United States. The causes for the backwardness of the United States in this regard are several, and first among them has been the abundant supply of cheap raw fuel with which the manufactured article has to compete. With our millions of acres of coal-productive territory, from which the product can in most cases be cheaply extracted, it has appeared in many districts more economical to waste the slack or culm, which con¬stitutes a considerable percentage -of the product, than to attempt to save it at the additional expense required for briquetting. It is for this reason that the view in all sections of the anthracite-region of Pennsylvania is marred by the unsightly culm-banks which encumber the ground, and that in some of the bituminous-districts one sees huge piles of unmarketable- slack allowed to burn up in order to get rid of them. When the coal is of a coking quality, or when the slack can be used for steaming-purposes, these losses are not sustained, but many thousands of tons of what might be converted into usable fuel have been wasted every year simply because of the increased expense involved in its preparation.

Sep 1, 1907

By Albert Hill Fay

IN giving a sketch of the geology and mining of the tin-deposits of Cape Prince of Wales, a short description of the geographic and climatic conditions may be of special interest on account of this being a part of the world of which very little is known, even by the reading public. As shown in Fig. 1, the location of the Cape is lat. N. 65° 35' and long. W. 168°. It is bounded on the north by the Arctic ocean ; on the west by Bering strait and on the south by Bering sea. It is the western-most point of the mainland of North America, and to the west, across the strait, one can see East Cape, Siberia, which consists of a rugged, steep coast of granite cliffs. The climatic conditions are of interest because of the part they have had in the surface geology, and also because they affect mining from an economic standpoint. In connection with the climate and geography, it does not seem out of place here to quote a few lines from the prologue of The Wandering Jew, written by Eugene Sue, under the caption '1 The Land's End of Two Worlds."

Sep 1, 1907

By J. Kent Smith

VANADIUM is generally spoken of as a rare element; but, even in the light of our resources as known a couple of years ago, this description could be accepted in a qualified sense only. In fact, vanadium is very widely distributed, being a constituent of most clays, while even caustic soda has been shown to contain almost regularly a minute proportion of it, although the quantity in each case is so small as to render impracticable the extraction of the metal there from with profit. The opening-up of a large deposit of vanadium sulphide ore in South America has put a new phase on the commercial outlook of vanadium, the technical value of which for the improvement of steel has been proved by rigorous scientific investigation.

Sep 1, 1907

By E. von Maltitz

IN his highly interesting paper on "Piping and Segregation in Steel Ingots,"1 Prof. Howe emphasizes the effect of successive phases of internal pressure in the ingot in the evolution of gas, and the consequent formation of blow-holes. From his statements in other places, it may be inferred that he does not here intend to ignore the other variable factor, temperature, but rather to discuss this one more particularly. At all events, it is my purpose not to engage in controversy with Prof. Howe, but rather to contribute, towards the complete elucidation of this important subject which we all desire, my own views and experience. If, in doing so, I specially emphasize other factors than pressure, I need not be understood as denying what I do not think it necessary to discuss fully. Nor, in presenting my own original conclusions, need I be understood as claiming to be the first who ever reached or announced them. Many things are asserted or suggested upon inconclusive evidence; and to confirm such tentative propositions may be as valuable a service as to overthrow them. In the following passage, Prof. Howe adduces analogies, based upon the behavior of charcoal and of water, respectively, which seem to me questionable "In general, the. solvent power falls as the pressure falls ; and in general it rises as the temperature falls. Thus, to heat a solid, for instance charcoal, may expel part of its dissolved gas ; and a tumbler of water drawn cold from the faucet gradually evolves gas, as it stands and warms up on the sideboard." (p. 238.) Charcoal is a solid body, which has the property not only of absorbing gases in large quantities, but also of expelling the thus absorbed gases upon heating. A comparison between charcoal and iron as to the absorption of gases is scientifically not possible ; the gas-content of charcoal is partly due to the

Sep 1, 1907

By WOOLSEY MCA JOHNSON

INDEPENDENTLY of the recognized chemical reactions involved in the production of metallic zinc, the process is affected by physical conditions in efficiency, and by commercial as well as technical economy. To offer some observations concerning these conditions is the purpose of the present paper. Among the important elements of this problem is the physical nature of the particles constituting the mass of zinc oxide to be reduced. This may be the result, either of the manner of the original deposition of the mineral, or of the treatment to which it has been subjected in the roasting-furnace. The physical character of the reducing-agent is another important factor, since the carbon of some coals is much more active in reduction than that of others. The degree of fineness, whether of ore or coal, or both, likewise plays a significant part. These factors, together with the physical admixture of foreign substances with the ore, may give rise also to chemical "side-reactions," sometimes hindering or retarding, and sometimes accelerating, the reduction. Finally, thermal conditions, including the relative conductivity of the materials, deserve to be taken into account. In firing a furnace with retorts charged with a mixture of roasted ore and coal, the first reaction is naturally the boiling-off of the contained water ; the next is the distillation of the light hydrocarbons from the coal; the next is the reduction of the iron oxide to protoxide and sub-oxide successively, and then to metallic sponge; and the final reaction is the reduction of the zinc oxide in the ore by the carbon to metallic zinc. This reaction commences at 1,022° to 1,060° C., according to the physical nature and condition of the coal and ore. Since the retort and the charge are far from being good con-

Sep 1, 1907

By John J. Porter

UNUSUAL problems have arisen at certain iron blast-furnaces in Virginia through the fact that the ore-supplies, derived from the Oriskany formation, contain from a trace up to 1 per cent. of zinc oxide. Since the technical literature bearing on this subject is very scant, the following notes, based on personal experience, will probably be of value to those of our members who are interested in iron blast-furnace practice. The course of zinc through the blast furnace is readily traced. Entering the throat as zinc oxide, finely disseminated through the ore, it descends unchanged to the fusion-zone, since a temperature of 1,000° C. or more is required for its reduction. At the fusion-zone, the zinc oxide is reduced by solid carbon to metallic zinc, which is set free as vapor and rises with the ascending gases to the cooler zones of the furnace. In cooling through the range of temperature from 1,000° to 500° C. the zinc is re-oxidized according to the reaction Zn + CO2 = ZnO + CO, and the resulting zinc oxide, being in a very fine state of division, is readily carried along by the ascending gases. Portions, however, deposit on the descending stock and are carried down, again to pass through the same cycle of changes. Still other portions deposit on the lining of the stack, and gradually form hard masses of "cadmia." Of the remainder of the zinc oxide, the greater part passes out of the furnace, and is either deposited in the down-comer, dust-trap, stoves, boilers and flues, or passes through the chimney into the atmosphere. A small portion escapes reduction and enters the slag as zinc oxide, while still another portion is absorbed into the lining of the furnace.

Sep 1, 1907

By WILLETT G. MILLERS

GENERAL RECEPTION COMMITTEE.-Willett G. Miller, Chairman; F. G. B. Alan, Hon. Frank Cochrane, Eugene Coste, Thomas W. Gibson, Cyril W. Knight, J. C. Murray, 0. N. Scott, Alan Sullivan, J. B. Tyrrell, J. W. Wells, A. B. Willis. COBALT RECEPTION COMMITTEE.-Arthur A. Cole, Chairman; Will. Ask with, R. W. Brigstocke, Robt. Bryce, Fred Coombs, M. I. Culbert, I. R. Drummond, J. W. Evans, A. Ferland, F. N. Flynn, E. L. Fraleck, S. R. Heakes, Joseph Houston, D. L. Jemmett, I. R. Jones, Major Leckie, Capt. Jack Leckie, R. W. Leonard, W. H. Linney, Alexander Longwell, Frank Loring, Murdock McLeod, John Martin, D. B. Rochester, W. E. Running. COBALT RECEPTION COMMITTEE (Ladies).-Mrs. A. A. Cole, Mrs. A. Edwards, Mrs. R. Jennings, Mrs. S. H. Logan, Mrs. A. Longwell, Mrs. H. F. Marsh, Mrs. J. Smith. SUDBURY LOCAL COMMITTEE.-Mayor L. O'Connor, Chairman; S. Fournier, Secretary; A. H. Beath, W. J. Bell, F. B. Bennett, D. M. Brodie, J. S. Buchanan, F. C. Busby, Wm. Chalmers, R. Dorsett, W. A. Evans, John Frawley, J. S. Gill, A. B. Gordon, J. G. Henry, T. N. Kilpatrick, Major Leckie, Chas. McCrea, John McLeod, Wm. McVittie, R. Martin, R. S. Mitchell, J. H. Morin, J. A. Orr, James Purvis (President Board of Trade), C. R. Reid, Major Smith, W. W. Stull, J. F. Templeton, S. E. Wright. The first session, held in the Banquet Hall of the King Edward Hotel, was called to order Tuesday, July 23, 1907, at 2.30 p.m., President John Hays Hammond presiding. Prof. Willett G. Miller, chairman of the General Committee, introduced Alderman J. J. Graham, who, in behalf of the City of Toronto, extended a hearty welcome to the members and guests of the Institute. To this welcome, President Hammond replied in a few well-chosen and hearty remarks. In the hall in which the session was held there was exhibited a fine, full-length, life-size portrait of Dr. Rossiter W. Raymond, in 1871 Vice-President and acting President, in 1872, 1873 and 1874 the elected President, in 1876 and 1877 Vice-President, in 1883, by appointment of the Council, and for the last 24 years by annual election, Secretary, of the Institute. Dr. James Douglas, of New York, N. Y., on behalf of numer-

Sep 1, 1907

By AIME AIME

As already announced, the XCIIId meeting of the Institute will be held at Toronto, beginning July 23, 1907. Hotel Headquarters will be at the King Edward Hotel, in which also the sessions will be held. The Queens, Rossin, Wallen, Iroquois and Palmer are good hotels not far from the King Edward. Members must secure their hotel-accommodations beforehand, by direct correspondence with the hotel they select. For those who neglect this precaution, the Local Committee will doubtless do what it can, but is unable to promise anything. Correspondence concerning this meeting (including notices of intention to attend it) should be addressed hereafter exclusively to Mr. W. G. Miller, Provincial Geologist, Bureau of Mines, Toronto, who is the representative of the Local Committee. The excursion to Cobalt, Lake Tenagami, Sudbury, etc., arranged by that Committee, involves the use of a special Pullman train for meals and lodging. After waiting a reasonable time to hear from members, the Local Committee has made its contract for Pullman cars. According to its latest report, there was still room for additional excursionists. Under this head, application made immediately to Mr. Miller may not be too late. Sessions for the presentation of papers, etc., will be held at the King Edward Hotel on Tuesday afternoon, July 23, and Wednesday morning and afternoon, July 24. The following papers have been accepted: 1. Sonic Reflections on Secrecy in the Arts, by James Douglas, New York, N. Y. .2. The Wilfley Table, by R. H. Richards, Boston, Mass. 3. The Tar-Sands of the Athabaska District, by' Robert Bell, Ottawa, Can. 4. The Occurrence of Nickel in Virginia, by Thomas L. Watson, Blacksburg, Va. 5. Coal-Briquetting in the United States, by E. W. Parker, Washington, D. C.

Jul 1, 1907