636 



NA TURE 



[October 24, 1907 



many years, of his patient and trenchant mind to 

 effect some real advance. The ideas to which he 

 most recurs are those of Delaunay and Gyld^n, to both 

 of which it is evident that he attaches high value. 



The paper No. 79, " Integrals of Planetary Motion 

 Suitable for an Indefinite Length of Time," supplies 

 a solution of the problem in outline, but in complete 

 and not in unfinished outline, so far as it is illustrated 

 by the system of Jupiter and .Saturn. 



The volumes are published by the Carnegie Institu- 

 tion of Washington. Vol. iv. contains an index, but 

 it is of the perfunctory character that makes it little 

 more than a list of names; Delaunay 's name is fol- 

 lowed by a list of no fewer than eighty-three reference 

 numbers, without other clue; it would be shorter and 

 equally useful to write Delaun.xy — passim. 



R. A. S. 



Stray Leaves and Some Fruit on Cancer, based upon 

 Physiologic Chemical Principles. By Henry D. 

 McCulloch. Pp. 49 + 3. (London :' John Bale, 

 Sons and Danielsson, Ltd., 1907.) 



The title of Dr. McCulloch 's book is original, and there 

 is no doubt as to the "stray leaves," but in our 

 opinion there is very little " fruit," and we find very 

 little of either " physiologic " or " chemical " prin- 

 ciples in the foundation of the heterogeneous collec- 

 tion of quotations which form the bulk of the book— 

 if, indeed, it can be said to have any foundation 

 whatever. 



In the present state of the cancer question, such 

 undigested material can only be another obstacle to 

 the real study of this most difficult of problems. .A 

 particular form of protozoal infection is assumed with- 

 out any proof, or mention of work on this theory, as 

 the cause of cancer; and the author thinks that " by 

 proper culture, and introduction to the leucocyte, a 

 vaccine or perfect remedial agent, vicariously prepared 

 in a living animal, will be possible." 



Dr. McCulloch makes an attempt to explain the 

 rSle _ of the leucocyte in the natural production of 

 specific vaccines in cancer. Certain leucocytes being 

 phagocytes eat up the opsonised microorganisms 

 under certain conditions, and return to the lymphatic 

 glands and there degenerate; their remains are pro- 

 pelled to the "gland reservoir," where a chemical 

 dissociation and rearrangement of their constituents 

 is brought about, and are finally converted into the 

 immunising agent. This occurs in the early stages 

 of cancer, which are not recognisable. When these 

 conditions fail, the leucocytes perform segregation, and 

 hence the metastasis in the cancer growth. 



The dissociation and rearrangement which occur, 

 according to the author, are said to be brought about 

 by enzymes. No doubt these play a part in the 

 process, and it might have been thought that the 

 author would have made an attempt to try to isolate 

 them, or, at any rate, determine what enzymes were 

 present. The assumption of an enzyme is not suffi- 

 cient proof for its presence, since enzymes are spe<-ific 

 in their actions, by which means they are identified. 

 A " nascent enzyme " has not yet been described. 

 The author has also introduced " hormone " in the 

 hope that the word may help to explain the unknown. 



The presence of so many quotations might have 

 included the following, by a distinguished phvsiologicnl 

 chemist : — " The less a physiologist knows about 

 cheniislry, the greater is his inclination to work at 

 the most diflicult chemical subjects — the proteins and 

 fermtnts. If even this subject be not sufficiently 

 obscure to him, he can study the phenomena of co- 

 agulation. He feels most at' home in the still more 

 obscure subiect of the pathology of coagulation and of 

 the ferments; it is good to fish in the dark! These 



NO. TqS2. VOL. 76] 



authors have built up a literature which no one can 

 become master of, and which is only a drag and a 

 brake to science." 



In this book of quotations, Dr. McCulloch finishes 

 up with one in .San.skrit, of which he gives a volu- 

 minous interpretation, which appears to have even 

 less to do with cancer than many of the many others 

 of which the book is made up. R. H. A. P. 



Helianthemum Canum (L) Baumg. und seine niich- 

 sten Verwandten. By Dr. E. Janchen. Pp. 68. 

 (Jena : Gustav Fischer, 1907.) Price 2.50 marks. 

 Helianthemum canu}n is a highly variable species, and 

 therefore one for which it is difficult to define the 

 limits. In the volume of Engler's " Pflanzenreich," 

 dealing with the Cistaceas, Dr. W. Gros.ser differen- 

 tiates two varieties that are each again subdivided 

 into several forms. The herbarium worker may follow 

 such a splitting of interrelated forms, but it is ex- 

 tremely unlikely that he could separate them in the 

 field where intermediate forms would probably be 

 found. Dr. Janchen puts forward an alternative 

 limitation of Heliauthcmnm canum, and one or two 

 nearly related species. Broadly, he merges in canum 

 part of the species recognised by Grosser as mari- 

 folium, and maintains italicum and rupifragum as 

 independent species. There appears to be considerable 

 support for Janchen 's arrangement, and the adoption 

 by Grosser of two varieties under different species as 

 H. canum v. marijolium and H. marifolium v. canum 

 is decidedly confusing, but the determinations of Dr. 

 Janchen are also based solely on herbarium material, 

 although a crucial test could be obtained either by a 

 study of the plants as they grow or by cultivating them 

 from seed. Undoubtedly, such methods are arduous 

 but not impossible, as all the plants under discussion 

 are European. It is only right to add that Dr. 

 Janchen himself recognises the necessity for deter- 

 mining the systematic limits in such variable species 

 by the methods indicated. 



Limnologia: Studio Scientifico dei Laghi. By Dr. 



G. P. Magrini. Pp. xy + 242; illustrated. (>iilan ; 



U._ Hoepli, 1907.1 Price 3 lire. 

 This valuable little work forms Nos. 372-373 of 

 Hoepli 's well-known scientific series of manuals. .\s 

 the title implies, it deals entirely with the phenomena 

 of lakes, and is intended to be preliminary to a some- 

 what similar work on the much larger subject of 

 oceanography. Limnology owes its name to Prof. 

 V. .\. Forel, whose standard monograph on the Lake 

 of Geneva is recognised as a model in this branch of 

 inquiry. The present volume deals more particularly 

 with the geographical and physical sides of the ques- 

 tion, touching but very lightly on the more difficult 

 subject of biology; it summarises the methods of ob- 

 servation which experience has shown to be the best, 

 including descriptions of the instruments used, the 

 improvements recently introduced in them, and the 

 principal results hitherto obtained. The occurrences 

 of seiclies are attributed partly to the sudden cessa- 

 tion of wind which had been previously blowing over 

 the lake, and partly to small differences of pressure 

 at various points of the lake (acting on the water as 

 on the mercury of a barometer); it is, however, pointed 

 out that although it may be possible to indicate some 

 of the causes that produce seiches, it is very rare that 

 the particular cause of any individual seiche can be 

 precisely determined. An appendix contains a list 

 of the positions and areas of the principal Italian 

 lakes. The author admits his especial indebtedness to 

 Profs. Forel and Delebecque, to whose works, and to 

 those of Prof. Chrvstal and others, frequent references 

 are made in the compilation of this useful manual. 



