Decembee 1, 1911] 



SCIENCE 



749 



emphasized by the papers that were read and 

 the discussions presented at the recent meeting 

 of the third National Conservational Congress 

 in Kansas City. It was intended that this 

 should be especially a " Soil Conservation " 

 meeting, and as such great prominence was 

 given to this topic. 



Ever since the settlement of this country, 

 its abundant soil resources have been drawn 

 upon, or there has been, as A. P. Grout 

 puts it, a literal " Eape of the Soil." The 

 fertility was earliest exhausted on the thin 

 soils of the eastern states, but it is only a 

 matter of time when the abundant cropping 

 will tell all over the country; and in fact the 

 important mineral constituents of the soil will 

 be practically exhausted. We are not a people 

 who can sit down and wait for nature, through 

 the slow decomposition processes and through 

 vegetation, to again render the soil fertile. 

 The chemist must come forward and show how 

 cheap phosphorus, cheap potash and cheap 

 nitrogen can be obtained. The physical char- 

 acter of the soil must be studied in order to 

 secure better cultivation and greater adapta- 

 bility of crops to environment. 



The water supplies of the country should be 

 more thoroughly understood. Not only must 

 the engineer utilize the pent-up mountain tor- 

 rents for producing power or for irrigation, 

 but the surface and ground waters must also 

 be used as domestic and municipal supplies. 

 The quality of this water should be known, 

 and the conditions favorable to maintaining 

 its purity are to be investigated in the labora- 

 tory. Again, with the growing manufacturing 

 industries, the industrial waste has to be taken 

 care of in some way so that the health of the 

 people be conserved, and the streams remain 

 unpolluted. If the sewage is allowed to enter 

 the streams, it must be so purified that it is 

 no longer sewage. Water-softening plants are 

 now deemed a necessity whenever the water is 

 not soft enough for laundry and domestic use. 



We realize that our wood supply is rapidly 

 wasting away, and there is need of care to 

 prevent waste not only in the cutting of timber 

 for lumber purposes, and in the precautions 

 against forest fires, but also in the utilization 



of the immense quantities of waste in smaller 

 limbs, roots and slabs. This, J. B. White 

 asserts, is often as much as 60 per cent, of the 

 tree. Here is an almost inexhaustible supply 

 of material which, as has been shown by G. B. 

 Frankforter and other chemists, may be util- 

 ized in the manufacture of charcoal, acetic 

 acid, wood alcohol, tar, resin oil, acetone, gas 

 and turpentine. The sawdust chokes the 

 streams and kills the fish; use it as a fuel or 

 for the manufacture of chemicals. 



In this same connection it is worth while to 

 notice that the need for so much wood in con- 

 struction has gradually been decreased by 

 using Portland cement. The chemist has 

 tested the limestones and shale, and can tell 

 where cement can be made at a profit. He 

 studies the market, the supply of raw mater- 

 ial and the cost of transportation of fuel for 

 a given locality. 



A few years ago our people went on the 

 principle that the supply of natural gas as fuel 

 was practically inexhaustible, but now that 

 they have begun to realize their error from the 

 shortage in many states, they are trying to 

 make the gas last as long as possible. Other 

 fuels are investigated by the chemist and we 

 are familiar with the use of " process-gas " 

 and petroleum burners. The " slack " from 

 the mines is molded into " briquettes," and 

 used as domestic fuel. 



That the " live-stock farm " will do much 

 towards preserving the fertility of the soil is 

 the belief of F. B. Mumford. It seems very 

 reasonable that if the farmer returns to the 

 soil the barnyard manure from his stock, the 

 more important chemical ingredients will 

 be retained. If, on the other hand, he sells his 

 crops, such as corn, wheat and hay, the land 

 will soon show signs of depletion. 



In the utilization of by-products no one is 

 more active than the chemist. He shows how 

 all the waste material may be utilized at the 

 packing house, how the whey from cheese man- 

 ufacture may be used to make milk sugar; 

 how the casein may be made into buttons or 

 dried and used in the arts ; how the cotton seed 

 may be utilized for making oil, and for a stock 

 food; how peanut oil may be used to take the 



