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By Tom Westgarth

As papers are placed before you upon large gas-engines in Belgium and Germany, it was considered that some information should be given upon the same subject in Great Britain. I therefore agreed to compile these notes, which I have made very short in view of the somewhat full nature of the other papers presented to this meeting, and considering the complete nature of the many publications which have been made recently upon the subject of large gas-engines. I give below Tables I. to VI., showing the number and particulars of large gas-engines which have been built or are building by British makers, and in view of the growing size of gas-engines I have concluded that engines less than 500 h.p. cannot now be included in the category of large gas-engines, and therefore I have not considered engines under that power.

Nov 1, 1906

By CHARLES HOPPER

In preparing the Steep Rock Lake iron ore body for mining, it was necessary to drain Steep Rock Lake. Using diamond drills, a cut 1800 ft long, 100 ft wide, and maximum depth of 95 ft amounting to 300,000 cu yd of material, was excavated in Greenstone to provide a drainage channel. This was done under the general contractor C. A. Pitts, of Toronto, who in turn employed a diamond drill contractor, Boyles Bros., to do the drilling. The method of excavation was selected be- cause a clean square cut and grade could be maintained in the bottom of the channel. Bootlegged holes would have left blocks of rock in the corners which would have created a situation which would have become progressively worse as the open cut advanced from one side of the ridge to the other.

Jan 1, 1949

Charles H. White, Harvard University, Cambridge, Mass, (communication to the Secretary*):—In answer to Mr. Jar-man's questions I am able to say that constant use (during term-time) since 1901 has shown the new appliances in our laboratory to be very satisfactory. The draft in the hoods is sufficient to lift the fumes promptly from the baths and hotplates ; and the occasional application of stove-polish,—usually about three times a year, at the recess-periods,—so well protects all iron-work in the hoods that, up to the present time, there is very little evidence of the corroding action of acid fumes. Iron should never be used in the construction of hoods above

Jan 1, 1906

By H. Kenworthy, M. M. Fine

The progress made to date in the mineral dressing of complex Arkansas titanium ores is reported in this paper. Concentrates of rutile, a dioxide of titanium, were produced by treating a submarginal ore from the Magnet Cove Rutile Co., Inc., Magnet, Ark. The rutile recovery at present is 45 to 50 pct of the total TiO2 with the possibility of increased recovery with additional research. The work reported herein is part of a general study which will later include results of investigation of other titanium ore bodies in the Magnet, Ark., area. The fragile character of the rutile minerals, the softness of the gangue, the occurrence of pyrite and leucoxene, and the considerable proportion of extremely small size rutile in the presence of montmorillonite- and illite- type clays in the Magnet Cove open-pit mine are the important factors in the mineral dressing of this submarginal rutile ore.

Jan 1, 1949

By W. L. Hill, W. H. Armiger, S. D. Gooch

The physical properties, chemical behavior under thermal treatment, and fertilizer value of fluorine-containing pseudowavellite (hydrous calcium aluminum phosphate) that occurs as phosphate clay admixed with quartz sand in an extensive deposit near Bartow, Fla., were determined by experiments in laboratory, pilot-plant, and greenhouse. When the mineral was heated at 500°C, 80 pct of the phosphorus became citrate soluble. The heated product, however, deteriorates markedly under moist conditions such as obtain in the soil.

Jan 1, 1950

Cooperation will be the keynote of the meeting of the Institute that will be held in New York on February 17 to 20. Arrangements are being made for two joint sessions with the Canadian Mining Institute, on the same day, which therefore will be known as Canadian Mining Institute Day. On the afternoon of Wednesday, February 19, there will be a joint session with the American Institute of Electrical Engineers. Besides, we will receive six or eight papers through the National Research Council, four of which will be presented at the National Research Council Session. In March, at the next meeting, of the Canadian Mining Institute, there will be an American Institute of Mining Engineers Day. The plan is to have the same subjects discussed at both meetings, but by different speakers. One speaker on each subject will represent the Canadian Mining Institute, and one speaker the American Institute of Mining Engineers. The Canadians and the Americans who will speak in Canada are expected to attend the discussion in New York. In addition the discussion at the New York meeting will be sent to Canada in printed form, so that the Canadian discussion will be a continuation of the former. At the joint session with the American Institute of Electrical Engineers, there will -be presented six very important papers on the subject of Electric Welding, one by the Chairman of the Electric Welding Research Committee of the National Research Council, another by the Chairman of the Metallurgical Sub-committee of that same Committee, and a third by Comfort A. Adams, President of the American Institute of Electrical Engineers and Chairman of the Welding Committee of the Emergency Fleet Corporation. We will receive six or eight papers through the National Research Council. These papers are results of recent investigations and represent the last word in their respective subjects. The excursion on Thursday, February 20, will be to Newark Bay to visit the Federal Shipyard where the first, electric-welded ship is being built. Philip W. Henry is chairman of the excursion committee of arrangements.

Jan 1, 1919

By AIME AIME

THE coal classification session* on Monday morning, Feb. 17, was opened by a paper by M. R. Campbell, entitled "Natural Groups of Coal and Allied Fuels," in which he pointed out, by means of graphical presentation of selected proximate analyses of coal, that coals can be classified on the basis of their moisture content. He proposes four groups of coal, brown coal, hydrobituminous, bituminous, and anthracite, each subdivided into two or three sub-groups. In a written discussion of this G. H. Cady, of the Illinois Geological Survey, showed that there is, in general, a progressive decrease in the moisture of Illinois coals from north to south, and that it would be very difficult to draw any arbitrary line dividing the coals of the State into two groups on the basis of moisture content.

Jan 1, 1930

By C. R. Fettke, Bela Hubbard

During the summer of 1916, while on a visit to the United States Agricultural Experiment Station at Mayaguez, Porto Rico, the writers were told by D. W. May, the director, that an occurrence of manganese ore had been reported from the mesa southeast of Mayaguez. A visit to the locality showed that the mesa is covered by a mantle of bright red soil resting upon serpentine. Here and there over its surface concretionary masses of limonite have been mashed out of this soil. These were apparently mistaken for manganese ore. On account of the similarity of this occurrence to the extensive iron deposits of northeastern Cuba, it was thought that a brief description based upon a two days'reconnaissance survey of the area mould be of scientific interest. Mayaguez is on the west coast of Porto Rico, at Mayaguez Bay, which is the third in importance of the harbors of the island. The city itself is about 3/4 mile inland on the low-lying plain at the mouth of the

Jan 1, 1920

By AIME AIME

PRIZES totaling $450 were awarded at the Annual Meeting luncheon on Monday, Feb. 9, to the winners of the third national student prize paper contest. The undergraduate prizewinners, each of whom received a check for $100, were as follows: Mayo W. Lanning, Lafayette College, for his paper entitled ?Some Aspects of the Mining Methods Employed at the Scrub Oak Mines of the Alan Wood Steel Company,? (entered by the Lehigh Valley Section). Charles F. Parent, Montana School of Mines, for his paper entitled ?Relationships of Manganese Minerals in the Butte District,? (entered by the Montana Section). Harry Czyzewski, University of Illinois, for his paper entitled ?A Metallurgical Study of Cast Irons Used for Glass Molds,? (entered by the Chicago Section).

Jan 1, 1942

By W. Mostowitsch, H. O. Hofman

The mineral gypsum, CaSO4 + 2 H2O, has been used for many years as a sulphurizing and basic flux in several smelting-operations. Thus, in smelting oxide nickel-ore in the blastfurnace, it is commonly added to the charge to furnish the sulphur necessary for collecting the metal in a matte, and a base for slagging the siliceous gangue. In the concentration of lead-copper matte in the reverberatory furnace it has been used for years at Preiberg, Saxony,1 for a similar purpose, and for producing at the same time a copper-matte with less than 0.15 per cent. of Fe. The latest use gypsum has been put to is in the blast-roasting process of Carmichael-Bradford.2 The term " blast-roasting," given by A. S. Dwight3 to the Dwight-Lloyd method of roasting and agglomerating: is a happy generic term which covers the ground better than the " lime-roasting " of Ingalls5 or the " pot-roasting " of Austin: in that it leaves the operation independent of the character of the flux and the form of apparatus, and retains the characteristic feature of this class of processes—namely, that of using forced draft. In the Carmichael-Bradford process the dehydrated material, mixed with galena-concentrate, acts as a diluent and a flux. The process differs in this from the Huntington-Heberlein7 and the Savelsberg8 processes, in both of which limestone is used.

Jan 1, 1909

By F. J. Cuddeback

For low-head pumping of small quantities of water, the water jet, or hydraulic educter, has been used to advantage by Eagle-Picher Mining and Smelting Co. in the Tri-State district. Water-jet pumps are used for draining sumps and pockets up to 15 ft. in depth. They have been used very successfully when only moderate amounts of water are encountered in taking up bottom. A small, easily handled unit is desirable in this work, especially while opening and deepening a new stope. Small air pumps are convenient but can be used only on the day shift, when air is available. Obviously, a jet pump of smaller capacity but operating 24 hr. prevents lost time at the start of each shift. No tests have been made on their power efficiency, but admittedly it is low. However, for certain kinds of work this is offset by their handiness, low initial cost, low upkeep, and reliability. They will handle slime and sand without ill effect, and will continue to pump indefinitely on air. This foolproof 24-hr. performance has led to their continued use at some places even after electric pumps with better power efficiency could have been installed. The success of jet pumps depends largely upon a cheap source of high-pressure water. Owing to mine depths in the Tri-State district, pump pressures range from 100 to 150 Ib. per sq. in. In many mines it is common practice to handle the normal inflow water with triplex pumps ranging in size from 3 to 8 in. The pumps operate 24 hr. per day, and, in order to handle emergency conditions, are speeded slightly faster than necessary to pump the normal inflow. The sump level is governed by controlling the by-pass water with a butterfly valve and float. This method is somewhat wasteful of power, but permits the pumps to operate with a minimum of attention. Such an installation is visited once a day to check lubrication. Hence, if some of this water, normally by-passed to the main sump, were used to operate a jet pump, the power cost could be considered low regardless of efficiency. Figs. I and 2 show two water jets that have done satisfactory work. The one in Fig. 2, made up entirely of pipe fittings, may be of interest partially because of its novelty, but does better work than its appearance indicates. The pipe fittings for this jet as shown cost $2.20. Some improvement in its design may be made by cutting out the 135 by 1¼-in. reducer to a smoother taper as shown by dotted lines. A 3-in. suction pipe is sometimes used in order that the discharge may be as straight as possible. A 2-in. discharge line has been used frequently, but 3-in. pipe is used where several hundred feet of discharge is required.

Jan 1, 1946

By W. H., Bassett

IN January, 1926, the writer began a study of the commercial value of beryllium in its relation to copper. The purpose of the investigation was not to make a mere laboratory study of the characteristics of beryllium-copper alloys, but to determine under mill conditions the behavior of copper when alloyed with beryllium and when other metals were added to such alloys; in other words, it was considered important to know whether the alloy bars could be hot-rolled or cold-worked, and what limits in composition would have to be established for these two methods of working. Consequently, more stress has been placed on the practical application of the alloys in engineering and commercial use than on a discussion of the metallography of the specimens examined, although this part of the matter has not been entirely neglected. Credit should be first given to G. Oesterheld,1 who, in 1916, published the copper-beryllium equilibrium diagram. Fig. 1 has been copied from the original article with the simple substitution of English words. It will be noted from Fig. 1 that alpha solid solutions are formed, up to about 1.5 per cent. Be (10.5 atom.). The freezing-point curve, after falling from 4.2 per cent. Be (23.5 atom.), enters into a very complicated form over the entire beta region. There is a possible compound, Cu2Be, at about 6.5 per cent. Be (32.3 atom.). The pure gamma range extends from 11.2 to 12.2 per cent. Be. (46.5 to 49 atom.), after which the liquidus rises rapidly to 30 per cent. Be. (75 atom.). The delta solution extends from 25 per cent. to an unknown percentage of beryllium. There is a eutectoid point at 575" C., extending from 1.5 to 11.2 per cent. Be., the maximum time interval of which occurs at 6 per cent. Be. Below this line the beta solution is described as breaking up into alpha and gamma. Microscopically, the eutectiferous alloy thus formed closely resembles pearlite, and requires a high magnification for its resolution.

Jan 1, 1927

By AIME AIME

IN accordance with the provisions of Art. XII, See. 3, of the By-laws of the American Institute of Mining and Metallurgical Engineers, the Board of Directors hereby give notice of their intention to amend the By-laws as follows : Art. V, Sec. 2. Amend by substituting the word "senior" for ('first" before the words "Vice-president" in line two of the third paragraph of said section which relates to the calling of special meetings of the Board in the absence or disability of the President.

Jan 1, 1930

TO THE BOARD OF DIRECTORS, AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS: Gentlemen.-I have the honor to present the following report of the President for the year 1919. In order that this report may be printed and distributed to the members in advance of the February meeting, it is necessary that it end with the calendar year 1919. Any activities during the first six weeks of 1920 will be covered in the Secretary's report for the year 1920. VISITS TO MEMBERS Your President has visited each of the Local Sections of the Institute, with the exception of the ones at Washington, D. C., Tulsa, Okla., and the Nevada Section. These three sections have not arranged meetings at which the President could be present. In addition, your President, accompanied by President Jennings and Secretary Stoughton, in the year 1918, attended meetings of members in Minneapolis and Duluth, Minn., and Houghton, Mich. A dinner and meeting of the members in Pitts-burgh, Pa., was also attended, in company with the Secretary and your President also attended the meeting of Canadian Mining Institute in Montreal, in March, 1919.

Jan 2, 1920

By S. R. Goodman, Hsun Hu

The formation of secondary - recrystallization tex-tlires in cube-textured 18-8 stain less steel (Type 304) Ilas been studied at three temperatures. Prolonged annealing at 100°'C protluces a PredoninanGly (520) [OOZJ-type texture, which is related to the cube te.ture of the primary lnatrix by a rotation of approxivzately 22 deg around the [001] axis in the rolling direction. Annealing at 1200 or 1300°C facers the formation of the (123)[272/-type texture, which is related to the matrix texture by a [111] rotation of app.voxiniately 40 deg. These observations suggest that in the secondary recrystallization of cube-texlut-ed stainless steel an apparent actilation energy for growth is higher for grains related to the tncrtuix Og [111] rotations thun those reloted by [100] rotations. THE formation of secondary-recrystallization textures in cube-textured primary matrices of fcc metals has been studied widely by various investigators. For Fe-40 pct Ni alloys, Pawlek' and wassermann2 reported that the orientations of secondary grains were related to the cube texture by rotations of 30 and 38 deg around [001] in the rolling direction. However, Rathenau and custers3 found that, while in one Fe-48 pct Ni alloy, most of the secondary grains were oriented with respect to the cube-textured matrix by rotations around [001] of 26.5 deg, in another alloy of a different origin, the orientations of secondary grains were related to the cube texture by rotations of approximately 35 deg around a [lll] axis. Similar orientation relationships were also observed between the secondary grains and the cube-textured primary matrices of copper.4"a No attempt was made to differentiate these two types of orientation relationships; reorientation by either a [111] or a [100] rotation was considered to be equally favored. The present investigation consisted of a study of the secondary recrystallization textures in cube-textured stainless steel. It was noted that the secondary grains formed in stainless steel were considerably smaller than those of Fe-Ni alloys or copper. This offered the advantage that the secondary recrystallization texture could be determined by the texture-goniometer technique, and a more detailed study of the textural development during the course of secondary recrystallization could be made. The effect of annealing temperature on the formation of secondary-recrystallization textures was also investigated. MATERLAL AND METHOD It was shown earlier"-" that a strong cube texture can be obtained in 18-8 stainless steels by rolling at 800°C to produce the copper-type deformation texture, followed by annealing at 800" to 1000°C for recrystallization. To improve the cube texture for the present study, a commercial-grade 18-8 stainless steel (Type 304) was rolled at 800°C first to 5 mm (0.2 in.) thick plates. Three of these plates were then stacked and welded together along the edges into a sandwich assembly. After annealing at 900°C for 20 min: the assembly was finally rolled at 800'C to 90 pct reduction in thickness with reheats and end-for-end reversals after each pass. Only the central strip, which was reduced from 5.0 to 0.50 mm (0.7 in. to 0.020 in.) thick, was used. The chemical composition of the steel in weight percent was as follows: C, 0.06; Mn, 0.38: Cr, 18.71; Ni, 9.56: P, 0.011; S, 0.009; and Si, 0.39. The purpose of rolling the strip in a sandwich assembly was to prevent direct contact between the central strip and the rolls. It was observed earlier" that, when the strip was rolled at 800°C without being enclosed in a sandwich assembly, the cube texture obtained by subsequent annealing at 900" or 1000° C for recrystallization was largely confined to the central section of the strip, while most of the recrystallized grains formed in the surface section of the strip were not cube-textured. This was obviously due to the fact that the actual temperature at the strip surface during rolling, as a result of direct contact between the strip and the cold and massive rolls, was considerably lower than 800°C. By using a sandwich assembly for hot rolling, the cube texture obtained upon subsequent annealing for recrystallization was found to extend through the entire thickness of the strip. After rolling, the central strip was taken from the sandwich assembly. and cut into specimens. Prior to annealing. the specimens were etched to 0.25 mm (0.010 in.) thick. A tube furnace provided with a purified, dry argon atmosphere was used for annealing. Textures were determined by the reflection technique. using a Siemens automatic texture-goniometer and ZrOz-filtered MoKa radiation. With a time constant of 4 sec. the preferred orientation of the secondary grains could be measured satisfactorily by the integrated intensities. Both (111) and (200) reflections were measured, and corresponding pole figures were constructed according to the techniques described previously.10 The agreement between results deduced from these two reflections was excellent. RESULTS AND DISCUSSION Secondary-Recrystallization Texture due to Prolonged Annealing at 1000°C. Fig. 1 shows the primary-recrystallization texture of a specimen annealed at 1000°C for 30 min. A substantial improvement in both sharpness and intensity of the cube texture, owing to the present processing method, can be noted readily by comparing Fig. 1 with similar pole figures shown earlier in Refs. 9 and 11. Secondary recrystallization

Jan 1, 1967

By S. A. Mahon

AN interesting feature among the mining structures, on the Mesabi. iron range is the iron ore stacker erected in 1934 at the Mesabi Chief washing plant at Keewatin, Minn. It is built of structural steel, and carries a system of belt conveyors which collects the washed product of the plant and places it on a stockpile for subsequent shipment. Although the only one of its kind in the Lake Superior iron district, installations of similar nature have been used elsewhere in the handling of coal and gravel and in earthwork construction. The reasons for stocking Lake Superior iron ores may be as various and diversified as the methods used in building the piles. At the under¬ground mines the existence of the huge piles in evidence at each active shaft is due, principally, to climatic conditions in this north country where the shipping period is much shorter than the operating season. Conversely, at the washing. plants it may be desirable to stockpile washed ores because the shipping season is commonly of longer duration than the period during which the plants may be operated. Washed ores, and mixtures of which washed ores are a component part, have found high favor with the oper

Jan 1, 1935

By Roland Blanchard

Recent discovery at Mount Isa of copper mineralization in commercial amount at a depth of 1000 ft., coinciding with downward termination of ore at about the same depth within the larger silver-lead-zinc lenses that have been the standby of Mount Isa's production to date, has been cited as an example in support of mineral zoning. A previous paper by the author and Graham Hall1 furnished a detailed description of the geology of the ore at Mount Isa as exposed up to that time, but necessarily dealt mainly with the silver-lead-zinc mineralization. Most of the geologic facts that constitute the first half of the present paper were set forth in the previous one in much greater detail, with full supporting evidence for the facts cited. The large amount of underground development (approximately 20 miles) and the extensive exploration carried out by diamond drilling (100,000 ft.) at Mount Isa, added to extensive microscope work conducted over a period of years, both by the company's staff and by others, had made possible the calculation within fairly close limits of mineralogical composition of the principal mineralized block of ground down to 1000-ft. depth, and had established closely the mineral succession, with reasons for deposition of the various minerals in the patterns now occupied by them. The geologic facts as outlined in the previous paper remain as stated; but because substantial development within the new copper ore body and further exploratory diamond drilling within the new silver-lead-zinc area (Racecourse) have taken place since that paper was written, statements and figures relating to those two areas in the present paper supersede those furnished in the previous one. The recent work likewise has established more clearly the paragenetic relationship between the chalco-pyrite and galena. Evidence confirming the relationship is furnished in the present paper. The facts of ore occurrence at Mount Isa show Accepted Zonal Succession Silver sulphantimonides Galena Sphalerite Tetrahedrite Arsenical sulphides Chalcopyrite Pyrrhotite Mount Isa Succession I In the main but prob- Silver sulphantimonides ably not wholly Tetrahedrite I contemporaneous Galena Pyrrhotite Sphalerite Arsenical sulphides They show further: (I) that instead of the silver-lead minerals yielding to increased zinc in depth, the zinc yields to increased silver-lead; (2) no dovetailing of the silver-lead-zinc sulphides into chalcopyrite takes place; (3) despite the large amount of pyrrhotite deposited in the district (estimated at upward of 100,000,000 tons), its deposition took place under moderately low temperature conditions; (4) no evidence has been found for increase in temperature of deposition, with depth, to deepest exploration in ore (1475 ft.). The anomalous condition at Mount Jsa, both as to the unorthodox mineral succession and the largely unorthodox patteru of mineral distribution, is explained in the present paper,

Jan 1, 1949

By Roland Blanchard

Recent discovery at Mount Isa of copper mineralization in commercial amount at a depth of 1000 ft., coinciding with downward termination of ore at about the same depth within the larger silver-lead-zinc lenses that have been the standby of Mount Isa's production to date, has been cited as an example in support of mineral zoning. A previous paper by the author and Graham Hall1 furnished a detailed description of the geology of the ore at Mount Isa as exposed up to that time, but necessarily dealt mainly with the silver-lead-zinc mineralization. Most of the geologic facts that constitute the first half of the present paper were set forth in the previous one in much greater detail, with full supporting evidence for the facts cited. The large amount of underground development (approximately 20 miles) and the extensive exploration carried out by diamond drilling (100,000 ft.) at Mount Isa, added to extensive microscope work conducted over a period of years, both by the company's staff and by others, had made possible the calculation within fairly close limits of mineralogical composition of the principal mineralized block of ground down to 1000-ft. depth, and had established closely the mineral succession, with reasons for deposition of the various minerals in the patterns now occupied by them. The geologic facts as outlined in the previous paper remain as stated; but because substantial development within the new copper ore body and further exploratory diamond drilling within the new silver-lead-zinc area (Racecourse) have taken place since that paper was written, statements and figures relating to those two areas in the present paper supersede those furnished in the previous one. The recent work likewise has established more clearly the paragenetic relationship between the chalco-pyrite and galena. Evidence confirming the relationship is furnished in the present paper. The facts of ore occurrence at Mount Isa show Accepted Zonal Succession Silver sulphantimonides Galena Sphalerite Tetrahedrite Arsenical sulphides Chalcopyrite Pyrrhotite Mount Isa Succession I In the main but prob- Silver sulphantimonides ably not wholly Tetrahedrite I contemporaneous Galena Pyrrhotite Sphalerite Arsenical sulphides They show further: (I) that instead of the silver-lead minerals yielding to increased zinc in depth, the zinc yields to increased silver-lead; (2) no dovetailing of the silver-lead-zinc sulphides into chalcopyrite takes place; (3) despite the large amount of pyrrhotite deposited in the district (estimated at upward of 100,000,000 tons), its deposition took place under moderately low temperature conditions; (4) no evidence has been found for increase in temperature of deposition, with depth, to deepest exploration in ore (1475 ft.). The anomalous condition at Mount Jsa, both as to the unorthodox mineral succession and the largely unorthodox patteru of mineral distribution, is explained in the present paper,

Jan 1, 1949

By AIME AIME

A SPECIAL meeting arranged by the Petroleum and Gas Committee of the American Institute of Mining and Metallurgical Engineers was held on Tuesday and Wednesday, Sept. 21 and 22, in the Assembly Room of the American Annex Hotel, St. Louis, Mo. Preceding the first session on Tuesday morning, the members and guests were registered and presented with the usual Institute badges. The morning session was opened at 10:30 by Ralph Arnold of Los Angeles, Calif., Chairman of the Petroleum and Gas Committee. In his opening remarks, he suggested that the petroleum section specialize more and more on the technical problems of the oil industry and that an effort be made to enlarge the membership of the Institute among the technical men of the industry. The following program was presented : OIL FIELDS OF RUSSIA, by A. Beeby Thompson and T. G. Madgwick, of London, England. Presented by H. A. Wheeler; discussed by Arthur Knapp and R. VanA. Mills. This most comprehensive paper was one of what is hoped to be a series to be presented by some of our foreign members. It is by far the best description in English of the world-famous Baku and other fields of Russia.

Jan 1, 1920

By Ezequiel Ordonez

MOST spectacular of Nature's contributions to the making of the postwar world is the Paricutin volcano, in Mexico, which I described in the July issue of this magazine last year, a few months after it was born. Now, after more than a year of continuous eruption, it is still and perhaps will remain a comparatively small though no less interesting volcano. The cone on April 1 had an altitude of nearly 1200 ft. above the level of the small flat field from which it began to grow on Feb. 20, 1943. This cone is now almost entirely surrounded by the lava flows that poured out at different dates, from its base or from outlets on the slopes near its base. To the north and northwest these lavas were

Jan 1, 1944