562 



NA TURE 



[October 15, 189 1 



of several examples of rather mixed information. The 

 following paragraph occurs on p. 104 : — 



"Ordinary dextrotartaric acid, for instance, has pre- 

 cisely the same properties as laevotartaric acid ; but the 

 compound of both which crystallizes from their mixed 

 solutions on evaporation — racemic acid— has quite a 

 different character. The first-named crystallize anhy- 

 drous, the last hydrated. The simple acids do not 

 precipitate a solution of calcium sulphate. The com- 

 pound acid does, and so forth. Yet it should be em- 

 phasized that such differences only occur with solid 

 compounds ; race.nic acid behaves in solution like a 

 mixture of the two components. ' 



Seeing that this book is one of the very few in which 

 Van der Waals's work obtains the prominence which it 

 deserves, and which has been long delayed, it seems a 

 pity that pains have not been taken to make the account 

 accurate. 



On p. 67 the reader is led to infer that b in Van der 

 Waals's equation is the volume of the molecules ; the 

 true value of b is four times the volume of the molecules. 

 Again, on p. 90, it is stated that the equation "is 

 deduced only for the case where the volume of the sub- 

 stance is eight times as large as the magnitude (J";. 

 correctly given, this should be, "is deduced for cases 

 where the volume is greater than ibr ^ 



Admirable as may be the exposition of the theory of 

 solution from the advanced standpoint here taken 

 up, it may rightly be questioned whether the student is 

 fairly treated. The physical theory of solution, the 

 dissociation hypothesis, no one knows better than the 

 author, are still strongly contested : should the student 

 therefore not have heard a little more of the other side 

 of the question ? Particularly objectionable is the 

 application of such terms as Boyle's law. Gay Lussac's 

 law, &c., to solutions. In the opening chapters of the 

 book the reader is familiarized with the kinetic theory 

 of gases ; he is enabled to form a mental picture of the 

 mechanism which results in the pressure of a gas. How 

 he, or, indeed, anyone, can form a similar picture for a 

 solution, when the molecules of the solvent have also to 

 be taken into consideration, it is difficult to imagine. 

 By using for solutions a term such as Boyle's law, which 

 for gases is capable of a perfectly definite interpretation, 

 the real difficulty of the question is ignored, and miscon- 

 ception is almost sure to arise, especially in the case of 

 the beginner. 



We noticed in passing that, on p. 364, polybasic is 

 used for dibasic ; on p. 370, k^a = k'Ji^a should be 

 k^a = k^Iva. Frequently there is no distinction be- 

 tween the type of letters occurring in formulae, and that 

 in which the book is printed. Reference in the body of 

 the book to portions of formulae is therefore apt to lead 

 to. confusion, and in any case lacks clearness, as may be 

 seen on pp. 297 and 369. 



The work, from its very title, apart even from the 

 reputation of the author, will no doubt appeal to a large 

 class of readers ; as an English text-book of chemistry it 

 is unique. We venture to think, however, that if such 

 points as those indicated were attended to, particularly 

 the question of space, its sphere of usefulness would be 

 materially enlarged. J. W. R. 



' Physical Society Memoirs, i. 3, 453. 

 NO. 1 146, VOL. 44] 



UNITED STATES FISH COMMISSION 

 REPORTS. 

 Bulletin of the United States Fish Commission. Vol. 

 VI II. for 1888. (Washington, 1890.) 



IN 188 1 the Senate and House of Representatives of 

 the United States of America authorized the public 

 printer to print from time to time any matter furnished 

 to him by the United States Commissioner of Fish and 

 Fisheries relative to new observations, discoveries, and 

 applications connected with fish culture and the fisheries. 

 The printed matter was to be capable of being distributed 

 in parts, the whole was to form an annual volume or 

 Bulletin not exceeding 500 pages, and the edition was 

 to be limited to 5000 copies. 



Seven volumes of this important series have since been 

 published, and have been noticed in our pages. They 

 were com.posed chiefly of translations or republications of 

 articles on fish or fisheries which had appeared in Euro- 

 pean periodicals or as Slate documents ; extracts from 

 the official correspondence, with statistics of work done ; 

 and often of short articles of direct scientific interest 

 on American fish ; the whole forming a most valuable, 

 practical encyclopaedia of everything relating to the 

 economic study of fish. 



An eighth volume, dated 1890, but being the Bulletin 

 for 1888, has just been issued from the Washington Press. 

 The increased operations of the United States Fish Com- 

 mission during 1888 have made it possible to devote 

 almost the whole of this volume to the results of the work 

 of the Commission, and it will be found to contain matter 

 of considerable interest. The size of the volume has 

 beeh slightly enlarged, so as to afford room for larger 

 illustrations. 



Of the twelve memoirs or papers contained in this 

 volume, five relate to local collections of fishes. Mr. 

 Tarleton H. Bean gives notes on a collection made 

 at Cozumel, Yucatan : sixty species are enumerated ; 

 two new species are described and figured. Mr. C. H. 

 Bollman reports on the fishes of Kalamazoo, Calhoun, 

 and Antrim counties in Michigan. Mr. S. A. Forbes con- 

 tributes a preliminary account of the invertebrate animals 

 inhabiting Lakes Geneva and Mendota, in Wisconsin, 

 and gives some particulars of the fish epidemic in the 

 latter lake in 1884. Mr. C. H. Gilbert describes some 

 fish from the lowlands of Georgia. Mr. D. S. Jordan 

 gives a report of explorations made during 1888 in the 

 Alleghany region of Virginia, North Carolina, and Ten- 

 nessee, and in Western Indiana, with an account of the 

 fishes found in each of the river-basins of those regions. 



In a review of the genera and species of Serranidae, by 

 D. S. Jordan and C. H. Eigenminn, we have an enu- 

 meration of all the genera and species belonging to this 

 family found in the waters of America and Europe, to- 

 gether with the synonymy of each, and analytical keys by 

 which the different groups may be distinguished. One 

 hundred and nineteen species are admitted, and thirty- 

 four genera. This memoir is illustrated with ten plates. 

 Mr. J. W. Collins contributes a paper on improved types 

 of vessels for use in the market fisheries, with some notes 

 on British fishing-steamers ; and Mr. W. F. Page gives 

 an account of the most recent methods of hatching fish- 

 eggs. Mr. T. H. Bean reports favourably on the feasi- 



