June 20, 1913] 



SCIENCE 



949 



period of six years, are indications of the at- 

 tempts tbat are being made to bring together 

 between the two covers of a book the modern 

 knowledge in this field. 



Most of the recent books, however, are con- 

 tent to present more detailed accounts of re- 

 stricted phytochemical groups. Next to the 

 literature on the volatile oils, on the fatty oils, 

 and on the carbohydrates, which have received 

 special consideration, no doubt, because of 

 their industrial significance, the allvaloids have 

 attracted considerable attention. 



While the fatty oils and carbohydrates repre- 

 sent decidedly restricted groups of chemical 

 compounds, the volatile oils and alkaloids 

 represent much wider fields, chemically speak- 

 ing. Biochemically, however, these two groups 

 have been regarded as of much less im- 

 portance than the carbohydrates and fatty oils. 

 This has, however, not lessened their inherent 

 chemical interest, which has always been ap- 

 preciated. However, their physiological sig- 

 nificance has also grown with our increasing 

 chemical knowledge of the compounds of these 

 two groups. Physiological interest is no longer 

 restricted to skeleton-producing or energy- 

 producing materials. It has broadened and 

 by no means to the disadvantage of the science. 



It has been said that modern pharmacology 

 owes its existence to the discovery of the alka- 

 loids. Hence one is not surprised to find the 

 pharmacological aspect of the alkaloids re- 

 ceiving consideration even in a treatise that 

 is predominantly chemical. For the same rea- 

 son the pharmaceutical aspect of the subject 

 has been given due consideration by the au- 

 thor of the book under consideration. Tet 

 there is a purely phytochemical point of view 

 that deserves more careful study than it has 

 commonly received. 



That the author of " The plant alkaloids " 

 should follow conventional lines is possibly to 

 be expected. That he himself does not find 

 satisfaction in so doing becomes only too ap- 

 parent from various statements that might be 

 quoted from his introduction. From a purely 

 chemical point of view, the alkaloids, like all 

 other carbon compounds, should be classified 

 in accordance with the definition that organic 



chemistry is the chemistry of the hydrocar- 

 bons and their substitution products. Thus 

 the conflicts and the irrationalities of a 

 classification based on the so-called typical 

 groups would be avoided. From a botanical 

 point of view, the alkaloids of a family should 

 be considered together, totally irrespective of 

 the nuclei they are supposed to contain. Thus 

 and thus only can genetic relationships be 

 brought out satisfactorily. Such a treatment 

 not only proves satisfactory in the considera- 

 tion of a single phytochemical group, but it 

 tends to destroy the arbitrary boundaries of 

 these groups. 



Nevertheless, we welcome the author's new 

 treatise. It may be claimed that it would be 

 better to revise one of the older texts on the 

 subject. That such revision becomes neces- 

 sary very often in these days of great research 

 activity is apparent to all who have occasion 

 to use these texts. However, if a new text 

 brings the subject matter up to date, it, as a 

 rule, not only fulfills this important require- 

 ment, it is also apt to do more. It usually in- 

 troduces new points of view at least here and 

 there. For this reason we often welcome a 

 new text rather than the up-to-date revision 

 of an older one. 



E. K. 



THE TEMPESATUBE ASSIGNED BY 

 LANGLEY TO TEE MOON 



In his last publication on the lunar tem- 

 perature,^ Langley receded from his pre- 

 vious estimate " according to which the soil 

 of an airless planet at the moon's distance 



^ ' ' The Temperature of the Moon. From Ee- 

 searches made at the Allegheny Observatory." 

 National Academy of Sciences, Vol. 4, Part 2, 

 Third Memoir, 1889. Two editions of this work 

 were printed. One is said to be "by S. P. 

 Langley, ' ' the other "by S. P. Langley and F. W. 

 Very. ' ' To prevent misapprehension, I will state 

 that the memoir was the joint work of Mr. Langley 

 and myself. A note written by Mr. Langley, ex- 

 plaining that my name had been omitted from a 

 place on the title page with his own by an over- 

 sight noticed too late for correction, was, by some 

 irony of fate, tacked on to the wrong edition, the 

 one which did have my name on. the title page. 



