I N D U S T R I A L and
ENGINEERING
CHEMISTRY
NEWS EDITION
Vol. 31 C o n s e c u t i v e No. 34
PUBLISHED
BY
THE
AMERICAN
HARRISON E . H O W E Editor
CHEMICAL
SEPTEMBER 10, 1939
VOLUME 17
SOCIETY NUMBER 17
The Chemical Industry of South Africa W. S. Landis, American C y a n a m i d Co., 30 Rockefeller Plaza, New York, Ν. Υ.
Maize p r o d u c t s p l a n t , Germiston, Transvaal A FRICA is a land of strange contrasts— birds without song, flowers without odor, and rivers without water. Even stranger than the oddities of Na ture is the sight of a modern chemical processing plant in the midst of the vast brush which characterizes the African high plateau. Chemical industry is be ginning to play an important part in the industrial life of Africa. After traveling for days through the brush on the famous African strip roads, the sudden view of an industrial plant seemed strange, yet such a development was only to be expected. Africa possesses unlimited chemical raw materials and the gold mines of Johannes burg and other mining industries are enormous consumers of supplies of all kinds. Geology
Almost all of the country from the Equator southward is sedimentary, with scattered areas of igneous intrusions. T h e Zambesi River valley and the great Victoria Falls, with its several-hundredmile-lone gorge, cut through trap rock. North of the Zambesi limestone and dolo mite appear, and the great RhodesianCongo copper belt is in such a dolomitic limestone. Through Southern Rhodesia and into the Transvaal there is a long dyke of basic intrusive and in this area great de posits of chromite and asbestos occur. South of the Zambesi sandstone predomi nates, and in the Transvaal, at Johannes burg, are the great gold mines, the mineral ized strata being an extremely hard quartz conglomerate. The principal mineral product of Africa is gold and this industry has its center in Johannesburg. The stratum of sandstone and quartzite bearing the gold has been tilted by an upthrust and the gold-bearing stratum, which is about 90 to 40 inches
thick and crops out in the city of Johannes burg, pitches southward at an angle of 70°, though it flattens out somewhat as the depth increases. This stratum has been traced to the east and southeast for about 30 miles and found to be in the shape of an arc. Broken and disturbed territory prevents the reef from being followed fur ther in this direction. Correspondingly, it swings in a wide arc to the southwest, and it has recently been found, at moder ate depths, in places 100 miles distant. The most modern appraisal is that the reef will be discovered to be# saucer shaped and indications are that the" southern out crop may be found in the Orange Free State. The depth of the crater is un known since the deepest mine is only 10,000 feet, but the fact that the reef flattens out as depth increases lends weight to the saucer theory. The reef, as far as prospected, is rather uniform in gold content. The average of 65,000,000 tons of strata mined last year was 0.20 ounce of gold per ton. The mining problems in the deep mines are complex, first because of enormous rock pressures, and secondly on account of high temperatures encountered so far underground. About 70 per cent of the lineal face is mined, while the remaining 30 per cent is left for support. Air-condi tioning units have been installed in several of the mines and the difficulties of air dis tribution to the working faces are slowly being eliminated. Probably the greatest copper deposits in the world are located in Cape Province, Northern Transvaal, and on the Northern Rhodesia-Belgian Congo border. The reserves in the Rhodesian mines, of which three are now in operation and a fourth under construction, are enormous, the ore containing 3.5 to 4.5 per cent of cop per in sulfide form. In the Congo area 565
are three important copper districts, two containing a sulfide ore, and the third, a carbonate deposit. The carbonate prop erty produced its millionth ton of metal lic copper in 1937 and more than 500,000 tons are untouched. The mining opera tions are all open-cut and the ore con tains 10 per cent copper. One of the sulfide deposits, not yet opened, is be lieved to De larger than any heretofore discovered. Other unworked copper dis tricts, not on the lines of transportation, are known to contain enormous amounts of ore. The Transvaal is an important producer of manganese ore, shipping 750,000 tons annually, and extending from the Trans vaal into Southern Rhodesia are literally mountains of chrome ore. Adjacent thereto in Southern Rhodesia are great asbestos deposits producing the highest grade fiber known. Northern Rhodesia and the Congo both possess lead and zinc mines. The Congo produces tin, gold, vanadium, and cobalt. Cobalt is associated with certain of the copper ores, both in the Congo and in Northern Rhodesia. Slags of the copper ore are concentrated in the copper con verter, taken to the electric furnaces, of which there are eight in operation in the copper district, smelted down to a coppercobalt alloy, and shipped to Europe for refining. The Fischer-Tropsch process for the production of synthetic oils is us ing much of this cobalt as a catalyst. In the Congo are also deposits of cobalt ore which may be smelted directly to alloy. Three great coal fields have been opened up in South Africa, and a fourth awaits transportation facilities. Good coking coals are found in N a t a l A rela tively small field, overlying the gold dedeposits of the Transvaal and extending
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INDUSTRIAL AND ENGINEERING CHEMISTRY
VOL. 17, NO. 17
ores are mined as such and smelted in the electric furnace to the 40 per cent alloy. A modern electrolytic sine plant in Northern Rhodesia produces sulfuric acid on the grounds. Lead is also smelted at this plant. An extensive development of sugar cane and a number of sugar refineries are found in Natal. The molasses from these re fineries is shipped to Johannesburg to a small alcohol plant supervised by two young men who received their training at a distillery in Philadelphia. They pro duce ethyl alcohol, anhydrous ethyl alco hol, butyl alcohol, vinegar, several esters, and dry ice. They have a very interesting plant, and have overcome numerous handicape in obtaining satisfactory opera tion in this distant country. A maize products plant produces starch and corn oil. Maize is the prin cipal food of the native and is grown ex tensively in South Africa. Four large fertilizer plants, two in the Union ana two in Southern Rhodesia, meet the needs of agriculture for mixed fertilizers. The plants in the Union are Native dance orchestra mine workers. Cyanide drums are used as resonators provided with superphosphate units. The explosives industry is highly de on "chop·". veloped. Two large plants, one in the Cape and the other near Johannesburg, southward to the Vaal River, supplies boxes to modern zinc dust units operating fuel for the power plants which furnish under vacuum. Sampling and assaying supply the requirements of South Africa. current to the mines, but this particular are highly developed, but there seems to A synthetic ammonia unit is the basis of field is almost exhausted. One hundred be a lack of skilled physical chemists for their nitric acid production. Sulfuric miles east of Johannesburg is the largest control of some of the chemical problems of acid is made in contact plants, either from imported sulfur or from pyrites coal field in the Union. It supplies a treatment. noncoking coal to power centers and to Only one by-product coke installation residue from the mines. A small explo the populous district to the west. In recovering by-products exists in the Union, sives plant in Southern Rhodesia pro Southern Rhodesia, not very far from the and that is the government steel works at duces explosives from imported chlorates Zambesi, is a large field of coking coal in Pretoria. Coupled therewith are a modern and organic compounds. which the seam is more than 30 feet thick. blast furnace, an open-hearth furnace, One of the most interesting of the ' Thisfieldsupplies the partial requirements and electric furnaces. The plant is chemical developments is in the Congo. of the Rhodesian copper smelters, and the equipped to produce rail, shape, plate, and This is a rather interesting chemical plant, Congo supplements it with imported sheet steel up to limited sizes. It also producing for local consumption, and is European coke of better quality. nearly 1200 miles by rail from the nearest contains a galvanizing plant. The great diamond fields extend east Beehive coke is made in two other coal port. At this chemical center there are ward from the mouth of the Orange River, fields in South Africa. Apparently there two large contact plants for sulfuric acid across the Orange Free State and the is no incentive to add the by-product used in copper leaching. These are Transvaal. Mines have been opened at equipment, although this is probably platinum silica gel units and, until a two points—Kimberly and Pretoria. The only a question of time as the country year ago, used imported Louisiana sulfur. Kimoerly pit is the largest man-made hole affords an excellent market for light oik More recently they have utilized a highin the world, although there is evidence and road tars. grade zinc blend produced locally. The of a prehistoric copper mine in the north There have been no petroleum or powder used in the Congo is of the chlo ern Transvaal which may have been even natural gas discoveries in South Africa. rate type. An electrolytic plant for the larger. However, a large production of A plant near Johannesburg, however, is production of chlorate, caustic, chlorine, diamonds comes from the so-called al endeavoring to develop a process of and muriatic acid, and a fatty acid plant luvial workings where 2 or 3 feet of sur producing oil from the focal shale. Pro are also located in this center. With the face is disintegrated and sifted for the duction from this source is relatively small, exception of the sulfuric acid units, the stones. Diamonds are found as far however, and the plant is importing crude other divisions have small capacity be north as the Congo, but most of the work petroleum for refining in equipment ulti cause of the limited outlet for their prod ings are near the mouth of the Orange mately intended for the shale oil distilla ucts. River and in the Orange Free State. tion. Some leather is produced in the Union, The copper industry of Northern Rho and shoe factories are being started. Chemical Industry desia is essentially metallurgical. The There is a small textile industry in the South Africa produces about 15,000,000 ores are concentrated by flotation, the making, involving finishing operations ounces of gold per year. By far the larger concentrates smelted in reverberatories, of the simpler types. proportion is obtained by treatment of the and the matte blown to blister copper in One email paper mill operates near ore with cyanide, followed by precipita converters. Furnace refining suffices at Johannesburg, making wrapping paper tion and refining. Approximately 85 per one plant, but electrolytic refining is re and board from scrap. It produces a cent of this production comes from the quired at another. A modern electrolytic wide variety of products, since the de Rand from mines located in a narrow refinery is being enlarged. mand for any one is necessarily small. belt about 60 miles long. This is prob Cobalt production from the converter It has only a local market, as it is more ably the most concentrated chemical in slags is an electric furnace operation, the convenient for coastal districts to import dustry in the world with respect to value of slag being reduced by carbon and suf their paper by freighter. A new paper production. The original stamp mills ficient copper added to the charge to mill on the Reef is beginning operations went out of fashion in 1926 and installa produce a cobalt-copper alloy carrying 40 this year. It was financed by one of the tions since that time use tube mills. per cent cobalt. mining groups and has installed the Ball mills are new particularly in those In the Belgian Congo the oxidized ores Pomilio process. Cellulose will be de portions of the reef where the ore body are concentrated by flotation, leached rived from straw. It is complete in all itself does not furnish the right quality with sulfuric acid, and precipitated elec- respects and has a modern caustic and and proportion of grinding medium. The trochemically. It is curious to note the chlorine plant. It will undoubtedly find a older properties on the reef use selected deep purple of the spent solutions leav market tor its caustic in the soap indus reef material for the mill charge of pebble. ing the electrolytic tanks—a consequence try, which has long been established. Precipitation varies from the old style zinc of their cobalt content. Here also cobalt Whale oil is readily available at the The AMERICAN CHEMICAL SOCIETY assumes no responsibility for the statements and opinions advanced by contributors t o its publications. Published by the AMERICAN CBEWICAL SOCIBTT, Publication Office, 20th & Northampton 8ts.. Eaeton, Penna. Editorial Office, Room 706, Mills Building» Washington, D. C ; Telephone, National 0848; Cable, Jiecbem (Washington). Advertising Department. 332 West 42nd 8t., New York. Ν. Υ.; Tele phone. Bryant 9-4430. Entered as eecond-clus matter at the Post Office at Easton, Penna., under the Act of March 3,1870, as 48 times a year. Industrial Edition monthly on the first; Analytical Edition monthly on the 16th; News Edition on the 10th and 20th. Acceptance for mailing at special rate of postage provided for in section 1103, Act of October 3 , 1917, authorised July 13, 1918. 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SEPTEMBER 10,1939 ports, since the Antarctic is the prin cipal whaling center of the world. rAany smaller chemical industries have been started. Paints, lacquers, soap powders, and cleaiung compounds are made in the Union. There is a small natural soda industry and salt is pro duced in quantity from brines. The cement industry is highly developed in several sections of the country. The deep mining in Africa, both in the diamond nelds and in the Reef, are de velopments to which American engineers contributed greatly. Formerly, many Americans were in the gold fields around Johannesburg but today only a few re main. A great deal of American equip ment was originally used in the mills but most of the machinery is now manufac tured in England. However, an indus try capable of building the ordinary mill equipment is slowly developing in South Airica. Shoes, dies, and balls for crushing equip ment are manufactured locally. Hoist ing cable is all of South African production and some real cables are used there. Over the central Reef are many shafts more than a mile deep, some of them six and eight compartments. On one of the deeper shafts, some 5400 feet vertical drop, the hoisting load is 32 tons and wit inn 12 seconds a hoisting speed of 4200 feet per minute is reached. The writer has dropped a mile at a rate of 3800 feet per minute and the drop was as smooth as in a normal office building elevator. The Northern Rhodesian copper fields are run largely by American engineers and mill superintendents. Americans originally were prominent in the Belgian Congo but in recent years they have prac tically all been displaced by an excellent type of Belgian administrator and engi neer. The equipment is either of Ameri can origin or of local production on Ameri can patterns. The remoteness of this copper district from large industrial cen ters requires that these mines be equipped with enormous shops, including foundries, and they carry immense supplies of structural and other steel. They are equipped to dismantle and rebuild any piece of mining machinery from a locomo tive to a copper converter. It must be remembered that the usual route to the coast is 1800 miles of rather slow railway. This, plus an additional β to 8 weeks to a European port, makes it necessary to be independent in the matter of machinery replacement. Yet this district is within 5 days of London by a twice weekly air service, and another service is being de veloped which will pass across the Sahara Desert into the Congo. One outstanding impression that will ever persist is the enormous amount of Dorr equipment one sees all the way from the Transvaal to the Congo. The Dorr representative has for years used his own private airplane to cover the territory. He can make the trip into the Congo in less than a day from Johannesburg, whereas by railway it is 6 days. Even the motor car is much faster than the railway.
NEWS EDITION with modern rolling stock, coal cars of 40 tons' capacity being the rule. Over the mountain grades they are electrified, and electrification is being developed in the Johannesburg-Pretoria area. Customs tariffs are relatively modest, butt railway rates are almost prohibitive on supplies for the mines. As a rule they nun about ten times more than similar charges in America. On the other hand, rates on farm products intended for ex port are ridiculously low. Railway rates, therefore, serve a more important purpose with respect to imports than does the customs tariff. Trucking is prohibited since it is competitive with the railway and in emergency it is only possible under special permit after depositing with the railroad the equivalent of the railroad rate. Arbitrary dumping duties are im posed. Therefore the relatively low cus toms duties play a minor part in the economy of import and export. There are good modern highways throughout South Africa, one being a through route from Cairo to the Cape. A second route to the Mediterranean is under construction. A comprehensive system of approved road building is in progress in the Transvaal and both the Cape and Natal possess many miles of excellent highways. In Southern Rhodesia the main high ways are improved with an interesting type of "strip" road. These highways are roughly graded and graveled. After being run down for a year or two a ma chine cuts a narrow groove a foot wide and about six inches deep in this highway, the grooves being spaced for the gage of the automobile. These grooves are filled with a tar macadam and rolled. They are passable in all weather and furnish a cheap means of extensive road building in a sparsely settled country. Passing is no obstacle, since the drivers auto matically swing over on one pad on the grades and at sharp intersections. Bridges and culverts are few, the road dipping, and in general the bottom of the wash is paved with the tar macadam preparation. In the heavier traveled sections a 9-foot roadway is paved. In the northern territories, including the Congo and Tanganyika, dirt roads are the rule. In wet weather they are not; always passable, and in dry weather they tend to corrugate. A favored top dressing is made from the ant-hill. The latter possesses an unusual binding property and rolls down into a firm, al most concretelike base. With the wide use of the automobile there should be an excellent market for road tars. An interesting side light on the in fluence of America is that practically all
567 of the motor cars, from the Cape to the Congo, are of American make. The English car is satisfactory in the cities, but does not stand up in interurban serv ice. This is where the American cars come into their own. Ford and General Motors have assembly plants in the Cape Province, and Firestone and Goodyear produce tires in the Union. My experi ence with South African-made tires, how ever, was a sad one, and they cannot be recommended for touring service. Ex· cellent mileage is obtained from wellknown American brands, although, be cause of preferential tariffs, they come fro.n Canadian factories. We traveled 5000 miles in 30 days in an American car with Canadian tires, and except for one alight mishap, on account of an attempt to drive at night, we had no difficulty whatever in negotiating the African roads. It was only necessary to drop the air pressure in the tires as we moved north ward toward the Equator, and again re place it as we traveled south. Gasoline costs from 45 cents an Imperial gallon in the Union to approximately $1.50 a gallon in some of the remote places in the Congo. Gas stations were rather infrequent over a part of this territory. In one place we were carefully informed that there was no gas or water for more than 150 miles. Nevertheless, there are courageous travelers who at tempt each year the trip from the Cape to Cairo, or the reverse, and this is quite possible in the dry season. During the rainy season there are likely to be periods when the roads are impassable, largely because of lack of bridges, culverts, or water so high that it is over the bridges. Night driving is not recommended be cause in the less settled portions much of the wild life congregates on the roads at night and becomes blinded by car lights. The animals in Africa are not disturbed by the motor car, and it is difficult to get them off the road after dark; in some places, even in the day time. A strict rule is to stay in the car and, except for the rhinoceros (if this precaution is taken) one need not concern himself about the animals. We carried no fire arms; in fact, we saw few animals if we stayed off the roads after dark. Motoring is certain to bring back memories of home, for the Shell yellow pumps, the Texaco star, and Socony symbols are ever present where gasoline is to be had. General
Another interesting occasion which brought back memories of the States, was the great tobacco auction at Salisbury in Southern Rhodesia. An auctioneer is
Transportation
I t is possible to land at the coast in Portuguese West Africa and by railway go inland to the Southern Congo and then all the way southward to the Cape. From this main north and south railway branches extend to the east coast through Portuguese East Africa and Natal and the Cape Province is rather well provided with railway service. Southern Rhodesia has an outlet through Beira, the Transvaal to Lourenco Marques, or a much greater distance to Durban. The railways are state-owned. They are all narrow gage, but well equipped
Copper dissolving and electrolytic precipitation plant. Jadotville, Congo
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INDUSTRIAL AND ENGINEERING CHEMISTRY
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imported from The writer was North Carolina remarkably im and the auction is pressed with the conducted in the work the Belgians same singeons are doing in the that one hears Congo to improve throughout the living standards. Carolinas. This The boys go to is not so strange trade schools and when it is realized receive an excel that most of this lent e d u c a t i o n . tobacco goes to a The native girls half dozen big are given an ele buyers who mentary training formerly traded in in household ecoour own southern nomics. They markets. The are taught to cook auction lasts and sew and as about a week and wives command a the tobaccos big premium over are the typical the kraal girls. " b r i g h t " , flue, There seems to and fire-cured be a great opporcigaret grades of t u n i t y in t h i s Alcohol and ester plant, Germiston, Transvaal our southern country for agri states. There I s cultural chemi some smoking tobacco produced of rather city like Johannesburg averages only cals. The soils of the high plateau of the about 25 gallons per white inhabitant good quality but success has not been Union are almost completely devoid of achieved in producing cigar and wrapper per day. The sewage, therefore, is ex phosphorus and, while it is a cattle country, tobacco. A test is under way in the extreme tremely concentrated and involves treat one never sees a bone lying in the fields. eastern part of Southern Rhodesia, which ment problems quite unknown in the The cattle are so starved for phosphorus may develop into an actual planting of this United States. Johannesburg has a mod that they eat these bones. Even humans latter grade. The South African is an ern system that services a large part of show phosphorus deficiency and under inveterate smoker, mostly using the pipe. the city. The city operates its own elec certain conditions teeth have been ab Pipe tobacco is good and very inexpensive, tric power plant and a new unit has been sorbed. There is only one small phos as that country is not quite so overbur set up at the sewage disposal plant which phate deposit in the Transvaal and though dened with taxes as our own. There are uses the effluent for water supply. Water it is of rather low grade an attempt is some half-dozen cigaret factories in South is very costly. At Johannesburg it has to being made to utilize it. Phosphates Africa. They are not permitted to treat be pumped 30 miles and elevated 2000 feet. must be imported from the Mediterranean the tobacco with the many chemical Every drop of water in this territory or from the United States. reagents that we use. since such addi south of the Limpopo River is utilized to Nematodes are a scourge. No good tions are considered adulterants. In the extreme. treatment of possible application has consequence» the South African cigarets Native labor is relatively cheap. Ια the ever been devised. In the tobacco dis are like the English type. The cigaret- Congo a good native boy for the house or trict two successive crops are grown on a making machinery is of the latest and the farm may receive only β or 8 shillings piece of land and then the punter must most modern type and operates at higher a month, plus a standardized ration and move to new soil. He cannot return to the speeds than much of the equipment in housing. The mines pay a higher rate, first plantation for about seven years. American plants. 12 to 15 shillings per month. Here the One of the smaller grasshopper nights In the union, modern plants have been boys are given every opportunity to> ac (known in Africa as locusts) occurred constructed for the production of serums, quire an education ana given manual during a cross-country trip. The grass antitoxins, and vaccines. This was neces training. They may serve in all positions, hoppers are between 3 and 4 inches long, sary because of the crowding in the gold such as locomotive drivers, mechanics, and are reddish brown. They travel in mines. The constant transfer of the down to common labor. In the Rhodesias dense masses, and actually stopped us on native from the mine, where he is per wages are slightly higher and no great the road for a few minutes while the flight mitted to stay only IS months, to the effort is made at education and training. was passing. The natives gather them, kraal calls for extreme care in sanitation. In the Union the labor unions have euch since they rain down on the ground like The housing compounds frequently have control over the government that the flies either from exhaustion or at the end as many as 5000 natives in one unit. native is only permitted training for cer of the life period, and feed them to the The natives come from the native villages tain limited services in the mines, and is stock, chickens, and even cook and eat and are put under quarantine and ob not allowed to become a skilled worker them themselves. servation for a couple of months, during in any of the trades. His education is Practically all kinds of pests thrive in which period they are schooled and practically nil and his pay runs about 3 this warm country, giving the entomologist taught to use certain tools. The native shillings a day in the mines, with some some very difficult problems. There are from the kraal is nourished badly because opportunities for greater earnings on piece some very clever scientists in this field who of his unbalanced diet. During such work. In the household he gets about have developed a number of ingenious quarantine he is built up physically by a 40 to 50 shillings a month. In all cases he control methods, but the problem is far scientific diet. He must be vaccinated must be fed and housed, or allowance from solved. The distance to market is for smallpox and may require other made therefor. On the farms the rates are an enormous handicap to agriculturalists, medical service. The greatest scourge is much lower. The native seems to nave and with the exception of special crops, pneumonia, largely because the men are great capability, if given the opportunity, such as citrus, farm returns are low, not now forced to five an indoor life and are and makes an excellent worker when allowing a great amount for insecticides. subject to great temperature changes trained. However, there is a large class The political situation of the Union is between the surface and the deep work of substandard whites that have t o he rather interesting. Natal is predomi ings underground. Woolen clothing is a taken care of and the law requires that nantly British; the Cape Province, not requisite. The surplus stock of American the mines hire one white for every ten quite to the same extent. The Free State army uniforms found use in this country. natives. These whites serve very little and the Transvaal possess large rural In consequence» the medical authorities useful purpose and are considered a great populations predominantly Boer, or better found it necessary t o set up an institution handicap. The theory is that unless Afrikander. Politically the rural districts for the production of biological prepara given special protection they would drop have a much larger representation in the tions based upon the strains incident to below the level of the native and give the legislature than the cities and in conse South Africa. There are excellent hos black man the ascendency. quence political control lies with the pitalization facilities in Johannesburg, and Afrikander. The country is officially Farm relief is also explained in that the the latest addition just completed for the mines have a limited life and they should bilingual, as the Afrikander refused to white employees is probably the most be heavily taxed to develop agriculture drop nis language for English. modern hospital in the world. It cost which will take up the slack as the mines With control in the hands of the Afri $2,500,000 without equipment. become no longer workable. Both theo kander who is essentially a farmer, farm All water supplies require treatment be ries read better than they stand analysis. relief has been developed to the highest fore bathing or drinking. One finds all for in the British- and Belgium-controlled degree. The cities and the mines foot sorts of treatment processes, filtration, territories they get along very well with the bill. Half of the profits of the mines chlorination, ozonation, etc. Water is so the native and have none of the restric goes to the State. scarce that the per capita consumption in a tions imposed in the Union. The country seems to be a land of great
SEPTEMBER 10,1939 opportunity. It is healthful in the higher parts» if even a crude sanitation is exer cised. In the low parts it is full of fever. The climate is suitable for whites, there being a large Belgian colony in the Southern Congo and a number of im portant towns populated by whites throughout the Rhodesiaa. Whites can live anywhere in the Union outside the lower river valleys or the desert. The mineral wealth is untold. Agri culture» however, is difficult over the greater part of this area. The whole country is accessible to motor car and the railways reach all important centers, al though the trains are very slow as the American looks at such tilings. It is undoubtedly the mostprosperous country in the world today. However, emigration to South Africa is quite difficult. Permis sion to settle in the country i s hard to ob tain and Datience is necessary while wait ing for the necessary permits. It is a country that once visited possesses an un usual attractiveness and all who have actually been in the country want to go back. M . I· T . Offers Course i n P l a s t i c s HE phenomenal development of the plastics industry and the great interest manifested in it by industrialists, chemists, and research workers have prompted the University Extension Division of the Massachusetts Department of Education to sponsor a course in the Industrial Chemistry of Plastics, at the Massachu setts Institute of Technology beginning Wednesday evening, November 8, 1939. Warren K. Lewis and Charles £ . Reed, professors on the faculty of Massachusetts institute of Technology in the chemical engineering department, have been ap pointed instructors in the course. The course will consist of 16 weekly meetings from 7:30 to 9 P.M. I t will be open to anyone interested, but will be particularly valuable to those engaged in the plastics industry, whether as chemists, manufacturers, or salesmen, or to those in other industries in which plastics may be an important factor in the future. The purpose of this course i s to bring out in a clear, practical, and nonmathematical manner the underlying eirnilarities in roperties and behavior of such supercially diverse substances as glass, the resins (both natural and synthetic), leather, rubber, plastic clays, ana the like. The course will be broad, basic, and funda mental in an attempt to establish firmly the general ideas underlying the correla tion of physical and chemical behavior with internal structure. After a review of the modern theories of the internal structure of matter, the fol lowing subjects will be considered: inter atomic and molecular forces which govern such important physical properties as plasticity, toughness, viscosity» tensile strength, elasticity, consistency; methods of measurement of significant physical properties; specific plastic materials of construction (including glass and ceramic ware), urea^formaldehyde plastics, vinyl resins, synthetic fibers (including both rayon ana nylon),alkyd resins, polystyrene, casein, adhesives, enamels, paints ana varnishes, artificial and natural leather and rubber, cellulose acetate, nitrate and ethers; the mechanism of the action of the filler, plasticizers, lubricants, dispersing agents, wetting agents, pigments, binders, and the like. Since this is a state-supported course, the charge made is nominal. Those inter ested may enroll at the first meeting of the class or previously by writing to the Divi sion of University Extension, Massachu setts Department of Education, Boston, Mass.
NEWS EDITION
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New Polaroid T e s t i n e Device TRAINS in glass rotameter tabes are S now successfully detected, both before and after installation, by Piaèhër fc Porter
Co., Philadelphia;'with a new Polaroid testing device developed by the engineers of the Polaroid Corp., Boston, Mass. Glass which is strained, either internally by faulty annealing, or externally by improper installation» may fracture when placed in service. Detection of such flaws is important as they may be corrected and eliminated, thereby obviating service breakage and attendant loss of processing liquids. I n the test, illustrated in the accompanying photographs, the tubes are simply held between the Polaroid eyepieces and the Polaroid field of the instrument. If the tube is free from external strain, it will show no change in appearance when it is placed in the test position. If internal strains are present they will show as brilliantly colored rings or streaks. Strains set up by improper pipe-line alignment are similar to those shown. The instrument is capable of showing an external force of only a few ounces.
Figure 1. Inspec tor examining ro tameter tubes i n this Polaroid-fitted polariseope.
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Figure 2. Left. To t h e unaided eye, two rotameter tubes look precisely alike, though one Is free from strain and t h e other h a s internal strain left alter annealing. Right. Two rotameter tubes viewed i n t h e Polaroidequipped polariseope. Tube a t left is free from strain. That with bands of brilliant light has rings of strain at critical point where tube will later be assembled i n complete rotameter. Instrumentation
Contest
HE second annual instrumentation T contest with a first prise of $200 in cash is announced by the Industrial In
strument Section of Scientific Apparatus Makers of America. Twelve prises in all, totaling $500, will be awarded. The contest is open to any person not employed by an instrument manufacturer. Two themes are specified: instruments save money; instrumentation makes jobs. The contestant is to submit either an original report or an original essay in support of either theme. No manuscript should cover both themes. The contest will be judged by the fol lowing Jury of Award: M. F. Behar, editor, Instruments: C. 8. Redding, president, Leeds & Northrup Co.; H. S. Richmond, treasurer, General Radio Co.; P. T. Sprague, president, The Hays Corp., and chairman. Industrial Instru ment Section 8. Α. Μ. Α.; L· G. Wilson, president, Precision Thermometer A In strument Co.; F. K. Taylor, vice presi dent, Taylor Instrument Cos.; Clemann
Withers, treasurer, Sperry Gyroscope Co. The contest closes November 15, 1930, and the judging will be held promptly. ~ - - rules - and nd official Copies of" the contest entry forms can be obtained from Scien tific Apparatus Makers of America, 20 North Wacker Drive, R. 3014, Chicago, 111. Glyptal U s e d as Exterior C o a t i n g HE first actual large-scale use of the alkyd resin Glyptal as an exterior coat ing has been in covering the copper on the exterior of the General Electric Building at the New York World's Fair. Thus protected, the copper has maintained its brilliant luster and characteristic color in stead of turning green or showing brown spots through natural exposure. Glyptal has been used for several years in paints and other coatings and among its general uses have been refrigerator en amels, automobile finishes, and other ex terior finishes requiring the utmost dura bility.
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