May II, 191 1] 



NATURE 





miert und dabei die einzelnen in ihrer Sondernatur 

 vernichtet (Summationsorgan) " (p. 292). Final 

 causes are postulated. " Ohne Beriicksichtigung von 

 Finalia ist ein Verstandnis auch der einfachsten 

 Amobenhandlung unmoglich." His account of in- 

 stinct, therefore, is through and through teleological. 

 The ends pursued are not to be explained from experi- 

 ence, on one hand, nor are they explicable in terms 

 of organisation as a product of evolution. They can 

 only be accounted for in terms of an "Allgemein- 

 bewusstsein," or "Weltvernunft," an absolute con- 

 sciousness. Kant and Hartmann are referred to 

 more than once, nor is Hegel omitted. Those men of 

 science to whom metaphysics is anathema, and those 

 (a class comprising much the same people) to whom 

 it is a terra incognita, will reject much of the book 

 as unsound. For others the book will be found full 

 of suggestions and new points of view. 



William Brown. 



SCALE MOSSES. 

 The Liverworts, British and Foreign. By the Right 



Hon. Sir Edward Fry, G.C.B., with the assistance 



of Agnes Fry. Pp. viii + 74. (London: Witherby 



and Co., 1911.) Price 2s. 6d. net. 

 TT is a pleasure to welcome the little volume on 

 -L liverworts, to which scale mosses, as well as 

 the more familiar Thallose forms, like Marchantia, 

 belong. Sir Edward Fry has long been known as 

 one who takes a keen interest in mosses, and this 

 new little book on an allied group of plants will 

 appeal to those amateurs who like to know some- 

 thing at first hand of the less easily studied objects 

 of nature. In truth, the liverworts are fascinating 

 plants, for they stand at the parting of the wavs 

 where the higher forms branch off from the lower 

 series of primitive groups. They are, however, not 

 easy to study, for they need a keen eye to detect 

 them, and they are, many of them, very difficult to 

 identify. 



Tlie authors have done good service in giving a 

 l)(.|)nl,n and attractive account of the family. The 

 \arii t\ (.f forms, no less than the suggestive differ- 

 ence- in their organisation, pointing as it does to- 

 wards higher vegetative development, will commend 

 the group as a whole to the attention of many who 

 may have avoided it on account of the difficulties 

 which have to be surmounted in making a first 

 icquaiiilance with the plants composing it. 



When the book is critically examined there are 

 not unnaturally points in which one mav differ from 

 the authors. The affinity between Calobryum and 

 Monoclea is really artificial, and they are not gener- 

 ally regarded as closely related. Recent work indi- 

 cates that the former is more naturally placed near 

 Ha])l()mitriuin. whilst a considerable difference of 

 opinion exists as regards Monoclea, some consider- 

 ing it as near the Marchantiaceae, others as belonging 

 to the Jungcrmanniacea? in the wider sense. 



As regards the origin of elaters, probably the 

 Riccia-Corsinia series affords a better clue than the 

 more s])ecialised Anthocerotaceae, but it mav perhaps 

 NO. 2167, VOL. 86] 



be argued that this is, after all, rather a matter 

 of opinion than of proven conclusion. We feel in- 

 clined, however, to take exception to the comparison 

 between the stomata of the grass-like sporophyte of 

 Anthoceros and those of the thallus of Marchantia, 

 which belongs to the other — the gametophyte — stage 

 in the life-history. The similarity between the two 

 organs is very slight, and although they perform the 

 same function the mode of origin is quite different 

 in the two cases. 



But these are small matters in a book which is 

 written for the amateur rather than for the professed 

 botanist, though the latter will also find it worth 

 reading. There are a few misprints which might be 

 corrected — one of them, Trichcolea for Trichocolea, 

 occurs several times — when a new edition is called 

 for. In the meantime, we can congratulate the 

 authors on having written an interesting little book 

 on a difficult series of plants. 



REFRACTORY MATERIALS AND PRODUCTS. 

 Fabrication et Eniploi des Materiaiix el Produits 



refractaires utilises dans I'Indnstrie. By Prof. A. 



Granger. Pp. iv + 378. (Paris Ch. Beranger, 



1910.) Price 15 francs. 



THE scientific study of firebricks, furnace blocks, 

 crucibles, and other refractory products is one 

 of increasing importance. The progress of metallurgy, 

 of glass-making, of pottery — even the development of 

 the domestic firegrate — demands scientific, as opposed 

 to rule-of-thumb, knowledge of refractory materials 

 and how they may be best applied to the requirements 

 of different industries, .\lthough many e.xcellent re- 

 fractory products are made in these islands, the scien- 

 tific study of the subject as a whole has received but 

 little attention as compared with that given to it in 

 Germany, France, and the United States. A few years 

 ago Dr. J. W. Mellor, of the Pottery Laboratory at 

 Stoke-upon-Trent, endeavoured to set up a committee 

 for the study and standardisation of firebrick and re- 

 fractory materials, and his work is now being carried 

 on, we believe, by a committee of the Iron and Steel 

 Institute, but it appears likely that some considerable 

 time must elapse before we have an English text- 

 book dealing with the subject as fully and as con- 

 cisely as this French work. 



Mr. Granger is well known as the professor of 

 ceramic technology in the school attached to the State 

 porcelain works at Sevres, and in all his works one 

 recognises the hand of the teacher who finds it neces- 

 sarv to compile a text-book for his students. This is 

 at once the strength and weakness of such a volume. 

 With the usual logical accuracy and perspicacity of 

 a French writer, the author gives an excellent review 

 of his subject. He treats of every variety of refrac- 

 tory material, fireclays, chromite, magnesia, and 

 aluminous products, including the newest materials 

 prepared for electric furnace work. 



The book contains a series of excellent illustrations 

 of tlie various forms of machinery especially adapted 

 for the treatment of fireclays, iS,c-., ,ind the chapter on 

 kilns and methods of firing, which are of extreme 



