July 4, 19 18] 



NATURE 



347 



sibly predict what the coal production of any 

 country will be a century hence, but, so far as 

 anyone can see, this rate of increase of production 

 Is much g-reate- than what the actual increase can 

 reasonably be expected to be ; it follows that 

 the present value of the coal resources is greater 

 on this hypothesis than it is in reality, even though 

 the value of all the production after the first cen- 

 tury be neglected. The value of the coal produced 

 during the century at 6(i. per ton, allowing money 

 to earn interest at the rate of 5 per cent., is only 

 about 550 millions sterling to-day, and though it 

 is impossible to assert that the coal resources of 

 Germany are really worth this amount, it is toler- 

 ably evident that they cannot be worth more. In 

 other words, the estimate of " Politicus " is nearly 

 400 times too great. 



Turning next to the iron-ores, the author puts 

 the quantity at 4000 mrllion tons, and he values 

 these at 55. per ton, apparently also at the mouth 

 of the mine, and thus gets at a value of 1000 

 millions sterling. Fully 80 per cent, of Germany's 

 iron-ore production comes from the minette ore- 

 field of Lorraine and Luxemburg, and as this 

 field is tolerably well known and much infor- 

 mation has been published about it, it will suffice 

 to confine the discussion to this field alone. 

 " Politicus " has taken his figures from those pub- 

 lished at the International Geological Congress in 

 1 9 10, but these are now out of date, and more 

 accurate data ^re to-day available. According to 

 the most recent estimates by the leading German 

 authority, the available minette ore in the Luxem- 

 l)urg-Lorraine ore-field amounts to about 2090 

 million tons. In 1913, the output was approxi- 

 mately twenty million tons, and it has been increas- 

 ing at the rate of about two million tons per 

 annum. Assuming a uniform rate of increase up 

 to the exhaustion of the field, which, though tech- 

 nically impossible, is a convenient hypothesis for 

 the purposes of calculation, and will assign 

 to the ore-field a value in excess of the facts, the 

 field would be worked out in about thirty-seven 

 years, the output in the last of these years being 

 calculated at ninety-two million tons. The esti- 

 mate of value given by "Politicus" is certainly 

 wrong ; these ores cost at the mine about 25. 6d. 

 to 35., 35. 6i. being considered a high figure. The 

 value of the ore in situ must accordingly be low, 

 though there are no data at hand for accurately 

 determining this; a valuation based on English 

 conditions would assign to it a value of 3d. to ^d. 

 Taking the higher figure, and again capitalising at 

 5 per cent., the present value of this iron-ore field 

 on the above assumptions comes to rather more 

 than i2i million pounds. If the discount on the 

 value of the ore to be won m later years had not 

 been taken into account, an erroneous value of 

 close upon thirty-five million pounds would have 

 b^en arrived at. Taking 3I millions sterling as the 

 value of the other iron-ores of Germany, a total of 

 sixteen million pounds is arrived at, and the 

 figure given by " Politicus " i's thus sixty times 

 too great; the error is less in this case than in 

 that of coal, because the period of exhaustion has 

 NO. 2540, VOL. lOl] 



been assumed to be much shorter, and the present 

 value, corresponding with the production at the 

 end of the term, is correspondingly higher. 



The third mater'ial discussed as a source of 

 mineral wealth is the series of potassium salts 

 derived from the vast deposits of which Germany 

 owns the practical monopoly. Here there are no 

 safe data available for determining the value. The 

 writer in the Fortnightly Review assumes that 

 the supplies amount to 50,000 million tons and that 

 they are worth 105. per ton ; as before, he has 

 confused value at the mouth of the mine with 

 value in situ, and has made no allowance for dis- 

 counting the sums realisable only at a distant date. 

 It is therefore probable that his figures are 

 several hundred — say, at least 2©o — times too 

 high, and that 125 million pounds is a more pro- 

 bable estimate of the true present value than the 

 figure given by him. 



Thus a correct method of appraising mineral 

 values shows that the figure of nearly 240,000 

 million pounds sterling, given by '* Politicus " 

 as the actual value of the three most important 

 items of the mineral wealth of Germany, must be 

 reduced to under 700 millions, so that the former 

 figure is roughly 300 times too great. It need 

 scarcely be repeated that the numbers here arrived 

 at make no pretence to accuracy, but they do prob- 

 ably indicate the correct order of magnitude of 

 the present value of these minerals, and, in any 

 case, they serve to show the correct method of 

 valuing minerals in their unsevered condition. 



H. Louis. 



ANTHRAX AND ITS PREVENTION .-^ 



ANTHRAX is an acute, infective disease of man 

 and animals and is caused by the anthrax 

 bacillus, which becomes disseminated throughout 

 the body so that every part is infectious. The 

 many animal products used in commerce may thus 

 be a grave source of danger if they emanate from 

 animals which have succumbed to the disease. 

 Although in this country anthrax is not to be 

 regarded as a frequent cause of death, it is never- 

 theless of great importance on account of the 

 increase which has taken place, and especially in 

 virtue of the very large amount of material 

 imported from countries where anthrax is rife. In 

 order to prevent the disease in dangerous trades 

 working with possibly infected animal material it 

 would, at first sight, appear to be a simple thing 

 to disinfect the infected material. In practice, 

 however, this is found to be exceedingly diflficult on 

 account of the truly enormous powers of resistance 

 of the spore of the anthrax bacillus, which is among 

 the most remarkable of living things. A method 

 to be efficient and practicable (i) must aim at 

 the complete destruction of the infectivity of the 

 material ; (2) must not damage the material ; 

 (3) must be practicable on a large commercial 

 scale ; and (4) its cost must be reasonable. 



1 Report of the Departmental Committee Appointed to Inquire as to the 

 Precautions for Preventing Danger of Infection by Anthrax in the Manipu- 

 lation of Woo',- Goat Hair, and Camel Hair. Vol. i., Report of the Disin- 

 fection Sub-committee. (London : Published by His Majesty's Stationery 

 Office, 1918.) Price xt. net. 



