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never attempt to do such work. The English and German physician examines all applicants for work and rejects the weakly and anemic. It is also the rule t h a t a man once really leaded shall not return to a dangerous part of the work. Here, I find in a great many places t h a t a man drops out because he is poisoned and goes home or t o a hospital, and when he has recovered he is allowed to go back to exactly the same sort of work. Of course in many ways it is much easier t o manage men who are of the same nationality as their foreman and who speak the same language, as is the case in most foreign factories. On the other hand, I was told t h a t the Italian help employed in one English factory were more docile than the Englishmen, who are sensitive about their individual rights and do not like t o be controlled as far as personal habits go. I t would certainly seem possible to make our men as amenable to discipline in the matter of cleanliness as in the matter of other factory rules. It may be asked, What is the result of all this elaborate regulation in England and Europe? I have been told by American manufacturers that there is actually less lead-poisoning here than over there. Fortunately i t is possible to answer that quite definitely. I n Cookson's plant in Newcastle where I 8 2 men are brought in contact with white lead, the most rigid weekly medical examination did not reveal one case in the year 1909 to 1910. I n Locke-Lancaster's place there was not one case among 9 0 men for the five years between 1903 and 1908;there was one in 1909. Let us look a t our factories now. I can give partial statistics of six places which manufacture white lead, a n d when I say partial, I mean that in none of these factories is the whole truth about the men known. Three of them have the physicians examine all of the men employed in handling lead, but do not follow up those who quit work-the English and German laws require this to be done-a third factory has a physician see only those men who complain or whom the foreman suspects of illness, the other two have no medical inspection and the only way I have been able t o find any cases has been through hospital records, and the men who go to hospitals are only the very severely poisoned, who have no families to care for them. These are the statistics: I n Factory No. I , medical examination showed one man in eight to be a t the time suffering from plumbism. I n Factory No. 2 , one man in nine. I n Factory No. 3, 28 per cent. of all employees have been leaded. I n Factory No. 4, where medical examination is only on complaint, 2 5 cases occurred among about 2 0 0 men, or one man in eight. The two factories which have no medical inspection' are sending t o a public hospital three cases and four cases respectively a month. This would mean 36 cases for one ' during the year and 48 for the other, but we know that not one-half of the leaded men g o t o the hospital and that the actual figure would be so much larger. 1
larly
One has recently engaged a physician to examine all the men regu-
June, 1.911
I n the whole district of Newcastle-on-Tyne there were employed last year in the white lead works, 1320 persons and only five suffered from lead-poisoning, or one for every 264 employed. In Illinois last year there were from 425 t o 450 men employed and we discovered sixty-three cases of lead-poisoning, or one for every seven men employed. This is a startling contrast and one that should make the American manufacturer stop and think.
POTASH FROM FELDSPAR. B y B. HERSTEIN, Technical Expert of the Tariff Board Received February 8, 1911.
The recent controversy between the German producers and the American importers of potash salt, a controversy which involved also the governments of both countries, has brought out forcibly the monopolistic privileges enjoyed b y Germany through the sole possession of potash deposits and has emphasized the fact that most of the other nations, our own preeminently included, have t o depend entirely upon t h a t country for their supply of this absolutely indispensable plant food. Irrespective of the economic aspect of the questions involved-and this is big enough even though we are accustomed t o figure in big units-it must be admitted t h a t the situation created b y such a condition is far from satisfactory, and has naturally led numerous investigators to work on the subject. I t seems t o have become an established fact that of the very few mineral deposits in which the United States, otherwise so bountifully provided, are deficient, potash in agriculturally available, i . e . soluble, form is one. However, potash in the form of insoluble silicate or aluminate makes up no inconsiderable part of the weight of feldspar and similar rock formation, and of these the supply in this country is practically limitless. As a plant food, however, the potash in this natural form is not assimilable and therefore of little value. The gist of all the many proposals so far made to secure from domestic sources the necessary potash salts required for agricultural purposes has consequently centered in the use of these rocks as raw material, differing only in the form proposed to render the potash available. The literature on the subject is fairly abundant and easily found in patent, technical or scientific publications. As far as the chemistry of the problem is concerned the field seems to have been covered fairly well, and in submitting an additional proposition in this direction, the fact is not overlooked that taken separately the individual features of this proposition may present little novelty, emphasis being laid on their combination, which is absolutely essential, and appears not to have been suggested before. Those who have given the subject more than casual thought know also t h a t the problem is more than chemical and more than commercial, and the plan is submitted here solely with the intention of broadening the legitimate scope of discussion by presenting possibly new and
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important features towards a solution t o a complicated problem. The chemical reaction involved in the process as proposed needs no further elaboration, having been proved in practice; it is in fact being used in somewhat modified form as a n analytical method for the determination of alkalies in silicates. I t consists in heating the finely ground feldspar with calcium chlorid eventually under addition of some limestone, whereby the silicate is decomposed with the formation of alkali chlorides-readily removable-and calcium silicate or aluminate. The process differs, as can be seen, from the well-known Lawrence Smith method only by the fact t h a t the calcium chloride is used here directly, while in the other the silicate is heated with a mixture of ammonium chlorid and calcium carbonate, which reagents form calcium chlorid as an intermediate product and thus bring about the decomposition of the silicate. Experiments have shown that the reaction can be carried through anddecomposition of the feldspar accomplished with little more than the theoretical amount of calcium chlorid if the ingredients are intimately mixed and the temperature well regulated and maintained for a sufficiently long time. Increasing temperature requires a corresponding excess of calcium chloride. Cushman, working along the same lines without adding limestone, seems t o have made the same experience and rejects the process merely because it is too expensive, as indeed it would be if there were no other considerations, to mitigate and outweigh this otherwise justifiable injunction. I n the first place, the calcium chlorid required for the reaction is a waste by-product obtained in huge proportions in the manufacture of soda ash and salt. It is less than valueless and the owner, if assured of a continuous outlet, could well afford to let it go a t a nominal price. Secondly, the residue left after the potash has been removed, by aqueous extraction or otherwise, contains all the essential elements of a cement into which it could be transformed by ignition, supplementing the deficiency of calcium oxid with limestone, if required. No previous grinding would be necessary in this instance, since with the temperature kept reasonably low, the mass does not clinker and disintegrates easily in water. Moreover, both the silica and the alumina of the original feldspar have been rendered extremely reactive and should therefore readily form cement on the subsequent operation. Another way to carry out the process would be to combine the two stages into one, i. e . , add limestone and a n excess of calcium chlorid to the finely ground feldspar and heat the mass to clinkering, whereby the potassium chlorid would be driven out by the higher temperature and could be collected in a suitable way. The heat prevailing in a rotary cement kiln should prove amply sufficient to produce this result. The cement clinker would be formed simultaneously with the distillation of the alkali chlorid and would need only final grinding. In this form the process would not differ materially from
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the ordinary way of making cement except in the presumed condensation of the alkali chlorid. The plan as outlined, if feasible in any form, would accomplish: I . ' The utilization of the valueless waste product, calcium chlorid, which a t present is but a source of annoyance and expense. 2. The production of cement. 3 . The production of potash salts for both industrial and agricultural purposes-a combination of three important features which should bring the proposition within the range of practicability. The plan is embryonal, of course, as any plan of this character, based mostly on a priori consideration, must be. The problems involved are vast and touch materially the interests not only of great industries but presuppose also careful consideration and cooperation on the part of different sciences: chemistry, engineering, geology and-not the leasteconomics. The difficulties militating against the realization of any proposition to utilize the gigantic stores of potash compounds lying unavailable in the feldspar and similar rocks are great and should not be underestimated. A review of the more important objections may help to a better conception of the subject. First, as t o the supply of the principal raw material itself. Feldspar, it has been stated, is most abundant in many of the states and will undoubtedly be found in others. But, unfortunately, the deposits are compact only in isolated instances, more frequently, however, they are contaminated with quartz and the mineral requires picking before i t can be put t o its proper use. Also the percentage of K,O varies within wide limits, some being as low as 5 per cent. and even under, others about I O per cent., and some considerably above this figure. An average yield of 6 per cent., or 1 2 0 pounds of K,O per ton, would probably be a safe limit to calculate upon; and this would be ob. tained in the form of potassium chlorid. This is not the most desirable and therefore not the highest paid form of potash for agricultural purposes, yet i t is used very extensively. The above yield would correspond t o 190 of KC1 per ton of feldspar, the money value of which on this side of the Atlantic is a t present, according to the price set by the German syndicate, $4.jo. This sum is contingent upon one factor which requires consideration. The valuation of potash salts, a t least for the export trade, is fixed, quite arbitrarily it seems, by the German commission entrusted with this task according to the law passed last Spring by the German Reichstag, which abolished all competition for trade between the individual mine owners. The monopoly is most complete and it is fair to assume that we are paying monopoly prices irrespective of the cost of production. The fact that individual operators contracted to furnish potash salts for some years to come to American importers a t prices considerably lower than those fixed later by the commission, seems to support this interpretation, and the potash value of $4.50 per ton of feldspar holds true
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only as long as the Germans see fit to maintain their the eventual stake. But the problem is not purely present prices. commercial, should not and cannot be considered so As a potash proposition alone any attempt to utilize without ignoring the larger economic questions inour feldspar as raw material offers therefore little at- volved. The days of extensive agriculture-an anatraction because a return of $ 4 . 5 0 per ton would chronism under any condition in an age of chemistry barely more than cover the cost of the raw materials such as ours-have passed in this country through themselves, viz., feldspar, calcium chlorid, limestone natural limitations, and the years to come must see and coal. But each ton of feldspar is assumed in in the United States a rapid development of intenthe plan also to produce five and possibly six barrels sive agriculture if we don't want to become dependof cement of a n average value of $ 4 . 8 0 , which would ent upon other nations for some of our food supply bring the total returns up to $ 9 . 3 0 per ton of feld- and face all the serious consequences which such a spar. Is this sum sufficient to pay all the expenses condition implies. This means a more extensive and allow also some interest on the large investment use of fertilizers, more phosphates, more sulphuric t h a t would be required? I n aswer to this it could be acid, more nitrogenous compounds, and more potash pointed as a parallel that cement is now selling a t salts. Our phosphate deposits are enormous. Onenot much more than about $ 4 . 5 0 per ton, and yet half of the sulphuric acid made in this country, or at seems t o pay a t that price for the raw materials, cost present over I,OOO,OOO tons, goes into agriculture, of operation, etc., and only quite recently it has been and while the larger part is made from imported stated b y no less an authority than Dr. McKenna that pyrites, there is more sulphur driven into the air in the actual cost of materials and labor is about 1 2 cents our western smelters than all our requirements call per I O O pounds of cement. The $ 4 . 5 0 obtained for the for, not counting the rich and readily accessible sulpotash would, therefore,have to coveronlythe additional phur deposits in Louisiana. The fisheries and the cost of the feldspar, the cost of some 2 0 0 to 2 5 0 pounds slaughter-houses furnish vast quantities of nitrogenous of calcium chlorid. a small additional charge in opera- matter which are being steadily increased b y the tion, and the interest on the additional investment gradual enlargement of the numbers of by-product required to provide for the collection of the potash coke ovens. With the rational development of salts. All evaporation, i t is figured, is to be done water powers the fixation of atmospheric nitrogen by the waste heat of the kilns. Another item of on a large scale is only a matter of little time in this extra expense would undoubtedly be found in the country. No fear need therefore be entertained on t h a t heavier freight charges because the raw materials score. For potash salts alone, every pound of it, would have to be brought together from different we must depend on imports, paying a t present yearly localities which is not the case in the cement indus- about $ 8 , 0 0 0 , 0 0 0 , a sum which is bound to go on increastry. ing, even if the Germans should forego the temptaAn important factor to be considered is, to what tion to raise prices, which always goes with monopextent such a n undertaking would influence the olistic possession. To prevent this we would be absocement industry, which already faces serious compe- lutely helpless, unless through the adoption of some tition on the part of iron and steel manufacturers. plan for utilizing the latent potash in the rocks we devise Our present consumption of cement may be said to some means of checking such tendencies. By creabe about 65,000,000barrels per year, but is rapidly ting a new industry and developing our dormant increasing. The calculation as given above assumes resources more useful employment would be provided, for every ton of 80 per cent. KCl made, a produc- which are other considerations of importance tion of 44 barrels of cement. Last year's imports of not to be neglected in any economic appreciation of potassium chlorid alone amounted to over 160,000 the situation. tons, which, on the above basis, would be equivalent The problem as a whole, though fairly clear in its to ;,040,000 barrels of cement. Could such vast outlines, is yet far from being sufficiently concrete quantities be gradually added t o a market which to promise any development from individual initiaseems already overprovided, without creating an tive alone. I t is too broad and involves too many alarming disturbance? Can it be expected that far-reaching questions of science, industry and national within reasonable time things would adjust themselves husbandry to admit of a solution on the part of any t o the new conditions, or could this new industry be single person. I t is a national question and should established and maintained only by inflicting serious be treated as such. If any advance is to be made losses upon one already existing? a t all, it can come only from an authoritative body I n the face of these difficulties i t must be candidly of men commissioned to investigate the whole field admitted that from a purely commercial point of of the potash supply question in this country, a comview, i. e . , as a question solely of profit and loss, the mission to include men of science with minds pracproposition as outlined above is not very alluring; tical enough to distinguish between the economically nor for that matter any proposition so far advanced feasible and visionary or impossible, and men of looking towards the utilization of the potash in the business capable of weighing a question frow a viewfeldspar. The investment required and the risk as- point broader than merely that of profit and loss. sumed are unproportionately large compared with ___---
