J u n e , 191j
T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C R E M I S T R Y
little more rapidly to 280’ C., and then stopping the external heating until the temperature reached a maximum, when the heat was again applied and the distillation finished by raising the temperature as rapidly as possible t o a little over 400’ C., fine wood and sawdust could be successfully distilled. They give the results of some ten distillations, but do not give any for sawdust. These results show t h a t from IOO lbs. of wood they were able t o get about the following products: Acid liquor, 43.75 Ibs.; tar, 3.45 Ibs.; charcoal residue, 31.12 lbs.; gas, 21.68 lbs. ,4 specimen analysis of gas is given, which shows that IOO cu. f t . had a weight of 8.62 lbs., so that the yield per lb. of wood was about 2 . 5 cu. ft. The calorific value of the gas was given as 11,493 B. t. 11. per lb., and this figures out at 990 B. t . u. per cu. f t . The percentage analysis of the gas is given, however, as being : Heavy hydrocarbons. . . . . . . . . . . . . . . . . . . . . . . . . 8.16 12.32 Marsh g a s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.45 Carbon dioxide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Carbon monoxide . . . . . . . . . . . . . . . . . . . . . . . Hydrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nitrogen.,. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
35.08 10.94 2.05
From this analysis the calorific value is calculated as 436 B. t. u. per cu. f t . If larger wood were being used, more gas could be obtained by carrying on the distillation a t a higher temperature; but from what the authors say, it would be impossible to do this with sawdust, since it would burn up under this treatment and the charcoal remaining after the distillation was completed would be so fine that it would be impossible to keep i t from burning, unless the retorts were discharged into an air-tight chamber. ECONOMY I N REINFORCED CONCRETE I n a paper on “Economy in Reinforced-Concrete Construction” read by Mr. T. A. Watson before the British Concrete Institute on February 18th, and quoted in Engineering, QQ (191j), 246, i t was stated that while great savings can be made on retaining walls, it is generally not economical t o employ reinforced concrete for the external walls of buildings, as brick walls up to a thickness of 14 in. are cheaper, but t h a t when walls have to be thicker than this the use of reinforced concrete is advisable. As under the proposed London County Council regulations nearly all external walls need not exceed 14 in. in a framed building, it is probable that reinforced concrete walls for this purpose will soon cease to be used from the point of view of economy. With regard t o the economy of reinforced-concrete framed buildings outside the London area the economy is very considerable; inside the London area the London County Council, by their regulations, propose t o reduce it as much as possible. There are, however, opportunities to effect savings over a steel-framed building even in London. I n the construction of bridges, say up to 300 f t . span a t least, reinforced concrete is nearly always the most suitable material. There are, of course, exceptions, but the mere question of the cost of maintenance of a steel bridge seems enough t o condemn it. The question of maintenanceis also enough t o decide a n architect or engineer to choose reinforced concrete for the construction of, say, small water towers, coalbunkers, gasometer tanks, or any similar structure heretofore built in steel, and exposed to atmospheric conditions, even if reinforced concrete is not cheaper in the first instance. T H E RUSSIAN PEAT INDUSTRY The remunerative exploitation of the vast peat deposits which many countries possess has for years been the subject of many experiments and much labor, although the results, perhaps, in most cases have been somewhat disappointing. In no country, according to Engineering, 99 (I~IS),4 7 7 , is there a greater wealth of raw material of this kind than in Russia, with her ho,ooo,oooacres of bogs, about 6.7 per cent of the country’s entire European area. Efforts are now being made to encourage
543
the peat industry, which in some districts has attained t o a fair importance, although the bulk of the deposits are still left unexploited. A special section for peat exploitation has been formed under the Department for Agriculture, with a staff of experts, who in the first place are to examine and report upon the peat deposits near the railway stations and the large industrial centers The State owns a very material portion of the country’s peat deposits, which, where this is found practicable, are let to private contractors for a fee of from 4 to 6 cents per cubic meter of peat. Only a small portion of the production is retailed out, the bulk being worked by large industrial concerns for their own requirements of fuel. Some few years ago seventy large manufacturing concerns in Central Russia produced 1,230,000 tons of air-dried peat. The output averages 2000 to 2 j 0 0 tons per season per machine, and the cost of production, as a rule, lies between Sz.00 and 8 2 . 2 5 per ton. In Russia, as elsewhere, the use of peat fuel for locomotives is a t present much to the fore, and extensive experiments. are being carried on with a view to arriying a t a satisfactory practical solution. Pulverized peat seems to have attracted most attention, and the Russians are being guided, t o some extent a t least, by the results obtained in Sweden in this direction. .~~~~
IRON, COBALT AND CARBON ’
In a paper on cobalt steels, by Prof. J. 0. Arnold and Prof.
A . Read of Sheffield University, read a t a recent meeting of the (British) Institute of Mechanical Engineers, a comparison of the effects of cobalt and nickel in steel will be of interest, because nickel and cobalt have been commonly considered to be identical in their properties [Engineering, QQ (191j ) , 3631. Cobalt is not nearly such a great graphite precipitator as nickel. Cobaltsteel ingots can be hammered down to I-in. bars with only a very small separation of graphite, 0 . 0 7 per cent in the highest member of the series, containing 20.85 per cent of cobalt. In the case of nickel-steel ingots treated in exactly the same way as the cobalt-steel ingots, a small separation of graphite began with only 3 per cent of nickel, and when 7 per cent of nickel was present the precipitation of graphite amounted t o about 1 2 per cent of the total carbon. Cobalt carbide appears, then, to be much more stable than nickel carbide, a conclusion which is also borne out by the analysis of the carbide residues obtained by electrolysis from cobalt and nickel steels. Cobalt does not form a definite solid solution or cobaltide of iron like that formed by nickel, having a composition corresponding to the formula FejNi, which, with only 0 . 1 per cent of carbon present, registers a maximum stress of about 90 tons per sq. in., associated with a reduction of area of 4 j per cent. An alloy containing about 13 per cent of nickel, and, sap, 0.6 per cent carbon, is so hard that i t is impossible to machine i t , whereas in the present series of cobalt steels, in which the carbon ranged from 0.62 to 0.93 per cent, and the cobalt from about 2 . 7 to 20.9 per cent, all the alloys, without any annealing, machined with the gr.eatest ease. The hardness, as measured by maximum stress, seems, with equal carbon, to rise with the cobalt. A%.
MANUFACTURE OF LABORATORY GLASSWARE IN GREAT BRITAIN A very important stage has now been reached in the investigations made by British scientists into the question of the manufacture of glassware to replace the supplies which were formerly obtained from Germany and Austria. Early in the war the Council of the Institute of Chemists appointed a Glass Research Committee to conduct experiments with a view to establishing suitable formulas which should be available to British manufacturers willing to assist in making laboratory glassware. The chief aims of the research work, which has been going on continuously, were to produce working formulas for glass used in
