February 3, 1910J 



NA TURE 



393 



THE MANUFACTURE OF LEATHER. 



The Manufacture of Leather. By H. Garner Bennett. 

 Pp. xxi + 420. (London: Constable and Co., Ltd., 

 1909.) Price 16s. net. 



IN this worlc the author has attempted to produce a 

 volume which shall be a text-book to meet the 

 needs of candidates for the examination of the City 

 ^nd Guilds of London Institute, and for the degree 

 and diploma examination of the leather students of 

 the Leeds University. The book is also evidently 

 ■written for the use of the practical tanner who 

 possesses a limited knowledge of chemistry. We do 

 not think that the author has been altogether 

 successful. The proportion dealing with the scientific 

 aspect of leather manufacture (specially noticeable in 

 the chemistry of the tannins), and the chapter on 

 tannage of chrQpie leathers, stand out in brilliant 

 ■contrast with the other part of the book, particularly 

 with the somewhat sketchy and superficial chapters 

 dealing with the practical tanning of sole, belting and 

 Viarness leathers. 



The first five chapters deal with the nature of the 

 skins, fermentation, hides and skins, and water; the 

 author then passes to the first practical process of 

 leather manufacture, viz. soaking, describing the 

 various processes employed. He next deals with the 

 various methods of removing hair and wool, together 

 with a full description of the tools and machinery 

 used for the purpose. Chapter viii. deals with the 

 •deliming of hides, a process which has now become 

 universal, owing to the increased technical and scien- 

 tific knowledge. In chapters ix., x., xi., the author 

 •brings together in handy form the chemistry of the 

 tannins, the tanning materials and the methods of 

 ■analysis. The next chapter deals with the preparation 

 ■of the tanning liquors and the manufacture of extracts. 

 In this, the author has gracefully glided over a very 

 "important subject, and has not dealt with many of the 

 important changes which take place in the leaching 

 nor dealt with some of the most recent plants devised 

 for this purpose. The whole subject of extract manu- 

 facture is referred to in two printed pages, whereas 

 ■on such an important subject as the manufacture of 

 ■extract, which now forms almost 50 per cent, of the 

 ■material for modern sole-leather tannage, it might 

 tiave been expatiated upon at considerable length with 

 advantage to the student. 



The next chapters then deal with the tannage of 

 sole, belting and harness leather previously referred 

 to. In the chapters on the tannage of chrome leather 

 but little detail has been given for the practical manu- 

 facturing process of this leather. The author then 

 proceeds to the consideration of alum, fat, oil and 

 aldehyde tannages, and to drying of leather, finishing 

 of sole leather, currying and finishing of dressing 

 leather, the dyeing and finishing of light leathers, 

 and the finishing of chrome and other leathers. \ 

 special chapter deals with the enamelling and japan- 

 ning processes and the dressing of wool rugs. This 

 concludes the practical part of the book, at the end 

 of which is a short chapter on the analysis of leather. 



The scheme is comprehensive, but the author has 

 NO. 2IOI, VOL. 82] 



failed to bring out any novel feature which has not 

 been dealt with, at least equally satisfactorily, by other 

 authors. The work cannot be looked upon as a 

 standard text-book for the practical tanner, but may 

 certainly appeal to those who, having a knowledge 

 of practical leather manufacture, desire to study 

 further the scientific principles. 



The book is well illustrated by photographs of 

 machinery taken from the well-known illustrated 

 catalogues of leather trades' engineers. These do not 

 show the essential features of the machines, but arc 

 simply photographic blocks; in no case are the 

 essential principles of the machines described. 



MEMOIRS ON MARINE ZOOLOGY. 

 Liverpool Marine Biological Committee's Memoirs. 

 XVHL, Eledone. By .\nnie Isgrove. Pp. viii + 

 105; 10 plates. Price 4X. 6d. net. XIX., Polychajt 

 Larva;. By F. H. Gravely. Pp. viii + 79; 4 plates. 

 Price 2S. 6d. net. (London : Williams and Norgate, 

 1909.) 



THE editor— Prof. Herdman— is to be congratulated 

 on adding these two useful memoirs to his well- 

 known series. Miss Isgrove has given a clearly written 

 account of a common cephalopod, for which she 

 prefers to retain the well-known Lamarckian name 

 rather than to adopt the name Moschites, which is its 

 correct designation, according to the strict rules of 

 nomenclature. In the first part of the volume interest- 

 ing observations are recorded on the habits and food 

 of this octopod, and on the conditions under which 

 it has been found in the neighbourhood of Plymouth 

 and Port Erin, .\ttention is directed to the great pre- 

 ponderance in number of the females, the relative 

 proportion of the sexes of captured specimens being 

 about fiftv females to one male. In the following 

 sections of the book the author gives an account of 

 the external features and internal structure of the 

 animal, considering each system of organs in turn. 

 The morphology of the funnel, which is one of the 

 most characteristic organs of the Cephalopoda,^ is 

 worthy of more extended reference ; the sections which 

 deal with the foot and funnel contain no allusion to 

 the homology of the latter with the epipodium of 

 gastropods; this homology is merely parenthetically 

 mentioned, fifty pages later, under the description of 

 the pedal ganglia. The alimentary canal, the circu- 

 latory and excretory systems, the nervous and repro- 

 ductive organs, and the spawning are carefully 

 described, the account of the structure of the gills and 

 the anatomy of the nervous system being w^orthy of 

 special mention. In the section on the structure of 

 the retina, the author speaks of a nerve fibre instead 

 of a neurofibril, running along the axis of each retinal 

 cell. The memoir is well illustrated by means of ten 

 lithographic plates containing above eighty carefully 

 drawn figures. 



Mr. Gravely has essayed a difficult task, namely, to 

 give an account of the polychast larva; which may be 

 captured in the tow-net at Port Erin during the month 

 of July. The complete identification of many of the 

 larvae so obtained is impossible, since their characters 



