Dec. 13, 1883] 



NATURE 



147 



length through a desert in hot weather at the rate of a 

 mile a day. 



The other papers in this volume are : No. i, on " Pro- 

 visional Fortification," a study of defensive works erected 

 in a moderate time, and capable of extension and im- 

 provement, with examples from Adrianople and Tschat- 

 aldscha. Paper 2, on " Graduated Arcs for Heavy Guns," 

 contains an investigation of the errors in such arcs, and 

 the mode of laying guns correctly, in spite of such errors. 

 Papers 4 and 5 describe some blasting operations in Ber- 

 muda. Paper 6 describes bridges laid over the Cabul 

 River during the war in 1S79-S0. Paper 7 is on " Rail- 

 way Curves"; and Paper 11 contains "Tables of Ord- 

 nance Equipment." ALLAN CUNNINGHAM 



OUR BOOK SHELF 



Report on the Dyes afid Tans of Bengal. By Hugh W. 



M'Cann. (Calcutta, 1883.) 

 This Report, which is issued under the direction of the 

 Committee of the Bengal Economic Museum, originated 

 in the efforts made by Mr. Thomas Wardle to collect 

 information on the modes of dyeing the silks of India. 

 This information was asked for so far back as 1875, and 

 although the Indian Government were fully conscious of 

 the importance of instituting an exhaustive inquiry upon 

 the s.ibject, it was not until iSSo that an instalment of the 

 General Report was issued, and from this, for reasons 

 which it is here unnecessary to enter into, the dyes of 

 Bengal were omitted. Ur. M'Cann has doubtless done 

 the best he could with the materials at his command, 

 although there is a probability that the Report would 

 have been fuller and more free from errors had it been 

 possible to put together the information, which was 

 mainly collected in 1875-77, at a time when the officers 

 of the local governments and administrations through 

 whom the information was obtained were still resident in 

 their respective districts. As it is, the Report is avowedly 

 incomplete, and in many points already out of date. The 

 classification adopted is, in the main, the same as that 

 already employed by Mr. Liotard in the Report on 

 " Dyes of Indian Growth and Production " above referred 

 to, but with the difference that Dr. M'Cann has preferred 

 to give the methods of dyeing in connection with the 

 accounts of the dye-stuffs themselves, instead of referring 

 them to the fabrics which are dyed by them. The dyes 

 are classed according to the colour they afford when used 

 singly. One disadvantage of this arrangement is that 

 some dye-stuffs which are used both alone and also 

 in the preparation of compound colours are men- 

 tioned several times. Many of the dye-stuffs are 

 called simply by their vernacular names, as they 

 have not yet been botanically identified, and in many 

 of the cases in which the scientific name of the speci- 

 men has been given there is nothing to show how it 

 has been arrived at. In spite, however, of these imper- 

 fections, the Report adds considerably to our knowledge 

 of the tinctorial resources of India, although it must be 

 stated that owing to the delay in its compilation the 

 original object of the inquiry has been in a great measure 

 lost sight of The primary object of the inquiry was, in 

 fact, to obtain data upon which to base experiments with 

 regard to the possibility of developing and iinproving 

 methods of dyeing with native Indian dyes. Dr. M'Cann 

 expresses the hope that this project may be revived. He 

 is of opinion that among the vast number of Indian dyes 

 there are many that might be developed into flourishing 

 industries ; but he is equally of opinion that this develop- 

 ment will never take place through the native dyers them- 

 selves, who are content to follow the primitive methods 

 handed down to them by their predecessors. Dr. M'Cann 



suggests thai great results might follow if the Government 

 would send out to India one or two trained chemists or 

 scientific e.xperts in dyemg to conduct experiments with 

 the special object of developing native dyeing industries. 

 The number of properly trained technical chemists already 

 there is too small to hope for anything from them, nor is 

 it likely that iiriprovements will result from the private 

 enterprise of European firms. As it seems nowadays the 

 fashion to commend all such projects to the notice of the 

 City Companies, it may not be out of place to draw the 

 attention of the Worshipful Company of Dyers to the 

 suggestion. T. 



Lehrbuch der Vergleichenden Anatomie der Wirbelthiere. 



Von Prof. Dr." Robert Wiedersheim. Zweiter Theil. 



(Jena, 1883.) 

 We have on a previous occasion (Nature, vol. xxvi. p. 

 385) directed attention to the first part of Prof. Wieders- 

 heim's text-book on the " Comparative Anatomy of the 

 Vertebrata," which was published early in 1882. He 

 has now, by the publication of the second part, completed 

 the work, which forms a clearly printed and profusely 

 illustrated volume of 906 pages, with 607 well executed 

 woodcuts. The second part comprises a description of 

 the alimentary, respiratory, circulatory, urinary, and 

 generative organs of the Vertebrata, and the author tells 

 us in his preface that the entire work represents the 

 labour of si.x years. In his method of treating the 

 anatomy of the viscera, described in this part, he has 

 followed the same lines as in Part I. The description 

 of the modifications of each system of organs observed 

 in the different classes of vertebrates is prefaced by a 

 short chapter on the method of development of that 

 system, and the subsequent description is then based on 

 their developmental history. We can recommend the 

 book as giving an excellent resume of the subject written 

 in a thoroughly scientific spirit. 



LETTERS TO THE EDITOR 



[ The Editor does not hold himself responsible for opinions expressed 

 l>y his correspondents. Neither can he undertake to return, 

 or to correspond with the writers of, rejected manuscripts. 

 No notice is taken of anonyinotts corntnnnications. 



[The Editor urgently requests corj espondents to keep their letters 

 as short as possible. The pressure on his space is so great 

 that it is impossible otherwise to insure the appearance even 

 of communications containing interesting and novel facts.l 



Evolution of the Cetacea 



In the lecture by Prof. Flow er "On Whales, Past and Preseni, 

 and their Probable Origin," which appeared in your columns 

 ia June and July la^t, he contends for the evolution of these 

 animals from the Ungulata, and points to the Zcugtodons of the 

 older Tertiaries as predecessors of the Balanoftera, and as 

 representing an intermediate stage in such evolution ; and he 

 insists on tbe absence of cetacean remains from any Mesozoic 

 formations as strong evidence in support of this view. 



I wish therefore to inquire whether Prof flower has con- 

 sidered the evidence afforded by Palaocetus sedgwickii, so named by 

 Prof. H . G. Seeley from a set of anchylosed cervical vertebra; (one 

 of n hich he fignres), described by him in the Geological Magazine 

 for February, 1865, p. 54. 



Prof. .Seeley states that the specimens were obtained from the 

 boulder (chalky) clay near Kly, and that they were regarded 

 both by the late Prof. Sedgwick and by himself as derived from 

 either the Kimmeridge or the Oxford clay ; and he quotes the 

 opinion of Prof. Owen in the British Association re|)orts, in 

 his " British Fossil Mammals," and in his " Palteontology," that 

 they belonged to an animal of the IJolphin group. Prot. Seeley 

 himself regards this animal, for the rea'-ons he assigns, as "not 

 a cetacean of the Dolphin family, bul a true whale, its affinity 

 with the Bala-noptera being, he says, singularly el 'se" ; and he 

 concludes his description with a letter from a veteran student of 

 tbe Cetacea, the late John Edward Gray, Keeper of the Zoo- 

 logical Department of the British Museum, who, after pointing 



