54^6 



NATURE 



[February 23, 191 1 



raised, while in 1907 more than 480 million tons were 

 got. The consumption per head of population rose 

 twentyfold during this period. If this rate of in- 

 crease of exploitation went on the whole coal supply 

 would be exhausted in 150 years, but reasons are 

 adduced against so short a lile. The exact period 

 is unimportant. '* So far as our responsibility is con- 

 cerned," says the author, "it is immaterial whether 

 the coal will be exhausted in 150 years, 1500 years, 

 or 15,000 years. Our responsibility to succeeding 

 generations demands that we reduce its use to our 

 absolute necessities, and therefore prolong its life to 

 the utmost." The waste in mining must be reduced ; 

 it varies from 50 to 150 per cent, of the total amount 

 sold, and is often irrevocable. Many thousands of 

 tons of slack are thrown out and burnt in heaps 

 simply to get rid of it. The beehive coke ovens, of 

 which there are said to be some 95,000 in the States, 

 are declared to waste fully $50,000,000 worth of 

 material every year in comparison with the more 

 modern types that might be introduced. Mechanical 

 stoking effects a great economy. Finally, there is the 

 waste owing to imperfect combustion, neglect of 

 waste heat, and so on. Cheaper substitutes might 

 often be got ; gas engines are more economical than 

 steam engines, while great improvements are possible 

 in lighting. Two lines of reform are suggested : an 

 educational campaign, and legislation to control min- 

 ing rights and to make waste an offence. 



The increase in the output of petroleum has been 

 enormous. During the first nine years of this century 

 more than 1,155 million barrels of 42 gallons was 

 got, this being more than 50 per cent, of the entire 

 output since it was first taken from the ground. If 

 the present annual output continues it is estimated 

 that the supply will give out in about ninety years. 

 Much of the oil is exported, and a fair proportion 

 is used for power. It is suggested that exportation 

 should be forbidden, and the home consumption 

 should be restricted to lubrication and lighting. About 

 natural gas the author has some very strong things 

 to say ; the waste, he tells us, has been appalling. 

 Gas has often been tapped when oil was sought ; 

 instead of closing up the bores or utilising the gas 

 the wells were lighted and allowed to burn. '* In 

 some cases a well has been thus allowed to burn for 

 twenty years. . . . Some of the wells have been 

 allowed to burn until the rock has caved in so exten- 

 sively as to have become veritable flaming lakes. It 

 is estimated that in the Saddo field alone of Louisiana 

 some 70,000,000 cubic feet per day of gas are wasted, 

 burned without doing any good in any way to any- 

 body." Legislation to stop the waste never gets 

 through ; attempts are regularly made, but " some 

 unseen power greater than Governor or Legislature has 

 so far thwarted and palsied every effort." 



Turning now to iron ore, most of this occurs in the 

 region of Lake Superior, and at least half is in the 

 hands of one corporation. If the rate of exploitation 

 during the three past decades is maintained the high- 

 grade ores will be exhausted in about three decades 

 more. But the author has no special anxiety for the 

 future ; the ore is handled economically, low-grade 

 ores not yet profitable are stored instead of being 

 wasted, new deposits will probably be found as the 

 survey becomes more complete, and stone and cement 

 are being used in place of iron. 



With water the principles of conservation are 

 different. So vast a quantity of water falls on to the 

 land every year that absolute exhaustion is out of the 

 question ; what is needed is to utilise the supply more 

 fully. Water that has been used for domestic pur- 

 poses may be used for irrigation with great advantage, 

 as it now contains fertilising material. Water used 

 for power may later be used for domestic purposes, 

 NO. 2156, VOL. 85] 



for navigation, or for irrigation. At present, how- 

 ever, there is an actual exhaustion of the water suiJ- 

 ply. In some parts of the States the level of tlie 

 underground water has fallen ten to forty feet. We 

 ourselves are in a similar situation ; the water level 

 in the chalk round London is known to be falling, 

 and great drafts are being made on the water in the 

 lower strata. 



The original forests of th^ United States are esti- 

 mated to have covered some 1000 million acres, of 

 which one-half has gone. The amount of wood used 

 is enormous, but so great is the waste that only three- 

 eighths of what is cut appears in the final product. 

 Loss by forest fires is appalling, " Boxing " the 

 trees, i.e. cutting cavities in them for the purpose of 

 collecting turpentine, kills many of them. It is esti- 

 mated that the average growth on the forest land is 

 12 cubic feet per annum per acre, while the amount 

 taken is 40. The waste of timber is attributed at 

 least in part to the feeling that the natural resources 

 were illimitable, and could never in any circum- 

 stances give out. 



Lastly, the author deals with the conservation of 

 the soil. First of all, there is the trouble due to land 

 speculation, which no legislation has ever been able 

 to get over. Then there is the question of improper 

 cropping. No "one crop" system can last without 

 an adequate expenditure on manure, and whether the 

 one crop has been cotton, as in the south, or wheat, 

 as in parts of the north, the result in the end is 

 disastrous unless proper manure is added. Now all 

 experience is that sufficient manure is not added, and 

 so we find in parts of the States that most terrible of 

 all sights — derelict land. Spillman considers that in 

 more than half of the area of the States the fertility 

 of the soil has fallen. Recourse has been had in the 

 dry regions to irrigation, with the inevitable result 

 that trouble has arisen through "alkali," i.e. an accu- 

 mulation of salts in the soil to such an extent that the 

 plant suffers. Methods of control are slowly being 

 worked out, but for a long time to come difficulties 

 will arise from this source. 



Depletion of soil nitrogen is serious, but not beyond 

 remedy ; thanks to the work of Sir William Crookes 

 and others nitrogenous manures are now being made 

 from atmospheric nitrogen. Depletion of soil potass- 

 ium compounds is also serious, but again, is not 

 beyond remedy. The disquieting feature is the deple- 

 tion of the phosphates. Every year this goes on ; 

 whatever the crop and whatever the treatment a 

 certain amount of phosphate is taken up and sold off. 

 Phosphatic manures are required and are Seing used 

 at an enormous rate. Fresh deposits are being made 

 by birds on the guano islands off Peru, but how are 

 th,; birds treated? Coker in 1908, in his report to the 

 Peru Government, speaks of "the robbery of eggs on 

 a large scale in past years, the destruction of young 

 and old birds, and the disturbance of the birds in 

 their nesting grounds by the extraction of guano." 

 We are not surprised when he goes on to say that 

 there " has been a great diminution in number." 



Some of Mr. Von Hise's data may be wrong — he 

 always gives his references — but it is incontrovertible 

 that we are taking but little thought for the morrow. 

 No doubt we in Great Britain have not wasted natural 

 gas, but what about our coal? Who can defend our 

 Victorian grates — still much the commonest form, in 

 spite of better types recently introduced — and our utter 

 neglect of waste heat in our houses? There is no 

 evidence that our soils are becoming exhausted ; much 

 of the land is left in poor pasture, and gives us little 

 return, but at least it is storing up fertility for a 

 future generation. But then we are importing 

 enormous quantities of foodstuffs from abroad, some 

 of which, being fed to cattle, helps to fertilise the 



