326 



NATURE 



[May 12, 1921 



the arrangement, whereby the princioles of struc- 

 ture and the various theories connected with the 

 subject are condensed together in the introductory 

 section, together with the essential facts upon 

 which they are based. 



Here is an example taken from p. 16 : — 



" Kekule, and independently of him Couper 

 [spelt * Cooper '] , brought to light another most 

 important property of carbon, resulting from its 

 four equivalent valencies. They showed that 

 carbon atoms possess also the property of com- 

 bining directly one with another." 



No one reading this paragraph without pre- 

 vious knowledge would imagine that a theoretical 

 conception was being put forward to explain 

 certain facts, for none of the facts are forth- 

 coming. 



It is difficult enough in ordinary circum- 

 stances to impress upon the student the impor- 

 tance of separating his facts and his theories, but 

 where theories and facts are jumbled together in 

 this fashion the task is made well-nigh impossible. 



Although the treatise does not profess to take 

 into account industrial progress in the different 

 branches of chemistry or statistical data beyond 

 the year 191 3, it is obvious that a large amount of 

 additional information has been introduced — e.g. 

 on p. 236 there is an interesting account of 

 "Chemistry and the War," n which a descrip- 

 tion is given of the various " poison gases " and 

 their preparation. Moreover, the increase in bulk 

 in vol. ii. (Organic Chemistry) has made it 

 necessary to divide it into two parts. 



(2) The number of editions through which 

 Prof. HoUeman's text-book has passed and the 

 variety of languages into which it has been trans- 

 lated afford sufficient evidence of its continued 

 popularity. As previously stated, it is essentially 

 theoretical in character, with passing and rather 

 superficial references to the physical side of the 

 subject. We think the student would be well 

 advised to study this branch of the subject in a 

 special treatise on physical chemistry, where it 

 is treated in a more comprehensive and general 

 fashion. It is impossible for him to obtain ade- 

 quate information on the physical properties of 

 organic compounds from such scantv descriptions 

 as are given here. 



In conclusion, may we suggest that the obsolete 

 glass funnel and cone figured on p. 30 should be 

 replaced by a modern porcelain funnel, and that 

 an alternative and simpler form of melting-point 

 apparatus should be added to the one illustrated 

 on p. 31, which we believe was rarely, if ever, 

 used by its inventor? 



J. B. C. 

 NO. 2689, VOL. 107] 



T 



Forestry in the United States. 



(i) The United States Forest Policy. By Prof. 

 J. Ise. Pp. 395. (New Haven : Yale Univer- 

 sity Press; London: Humphrey Milford ; Ox- 

 ford University Press, 1920.) 215. net. 



(2) Forest Management. By Prof. A. B. Recknagel 

 and Prof. J. Bentley, jun. Pp. xiii-f 269-1- iii 

 plates. (New York : John Wiley and Sons, 

 Inc.; London: Chapman and Hall, Ltd., 1919.) 

 135. 6d. net. 



(3) Forest Products: Their Manufacture and Use. 

 By Prof. N. C. Brown. Pp. xix-t-471. (New 

 York : John Wiley and Sons, Inc. ; London : 

 Chapman and Hall, Ltd., 1919.) 215. net. 



HE wise use and the conservation of the 

 wealth of timber still existing in the 

 United States are promoted by a presentation of 

 the history, by a trained economist, of the effects 

 of legislation and Government administration on 

 the ownership and management of American 

 forests from Colonial days to the present time. 

 The author calls it " a story of reckless and waste- 

 ful destruction of magnificent forests, and of 

 flagrant and notorious thefts of public lands. " 

 The picture, however, is not so dark as this, 

 though the account of the frauds perpetrated 

 under cover of the Free Timber and the Stone 

 and Timber Acts of 1878, and of even later legis- 

 lation, is very startling. 



The idea of forest conservation is not modern. 

 In 1681 William Penn issued an ordinance 

 which enjoined the preservation of one acre in six 

 of the forests of Pennsylvania, while strict laws 

 against forest fires were passed by many of the 

 Colonies. These early measures proved ineffect- 

 ual. Real progress began with the Act of 1891, 

 which empowered the President to set aside forest 

 reserves out of the public domain still retained by 

 the Federal Government. This has been the 

 means of creating the National Forests, which 

 now aggregate 176,000,000 acres, under the con- 

 trol of a highly trained Forest Service. This 

 splendid work of conservation has been done in 

 the teeth of tremendous opposition, and even now 

 in some quarters there is continual criticism of 

 the policy and operations of the Forest Service. 

 It is, however, generally admitted that a careful 

 classification of all public lands is necessary, and 

 that only those which are fit for agricultural pur- 

 poses should be alienated. This principle will 

 preserve the National Forests. Prof. Ise's 

 treatise is an animated history of the struggle for 

 the conservation of the forests of the United 

 States, and deserves careful perusal by statesmen 

 and economists in our own Dominions and 

 Colonies. 



