Dec. 19, 1889] 



NATURE 



151 



the Birmingham and Midland Institute — is to be con- 

 gratulated on the good work he has done in this con- 

 nection. The book is illustrated with 72 figures, which agree 

 with the simplicity and clearness of the diction, and ques- 

 tions are found at the end of each chapter, which have 

 been well prepared to test the learner's apprehension of 

 its contents. We are pleased to be able to recommend 

 this little work, as a foundation for the study of the 

 metallurgy of iron and steel. 



OUR BOOK SHELF. 



On the Creation and Physical Structure of the Earth. 

 By J. T. Harrison, F.G.S., M.Inst.C.E. (London: 

 Longmans, 1889.) 



This book brings to mind one of the most winning of the 

 vagaries of childhood. A bright child of an inquiring 

 turn will sometimes sit with comical sedateness listening 

 to the talk of its elders. It may afterwards be overheard 

 repeating to one of its playmates, or to some lucky adult 

 who has the knack of winning its confidence, such 

 detached scraps of the conversation as have found a 

 resting-place in its little brain ; and, conscious even at its 

 early age of the necessity of some continuity in a narra- 

 tive, filling up the gaps with inventions or criticisms of its 

 own, charming every way, but mainly on account of their 

 utter want of connection with the subject of the conver- 

 sation which it is attempting to report. So our author 

 has listened to the teaching of many geologists, and has 

 culled many detached passages from their writings : these 

 he repeats to the world in a book, printing between them 

 omments and lucubrations of his own, about as innocent 

 ip.d as little apposite as the child's prattle — hardly so 

 amusing, however. The following passage is a fair sample 

 of the writer's own share in the book. " The termination 

 of the Secondary Period, which introduced these altered 

 conditions of the surface of the northern hemisphere, was 

 really the commencement of what is called the Glacial 

 epoch in Europe. We have noted signs of glaciation 

 during the deposition of the upper chalk in India and 

 North America, but now the conditions which induced that 

 glaciation are extended in such a manner as to unite 

 these districts, and produce that enormous accumulation 

 of snow and ice at the North Pole, the weight of which in 

 the Miocene epoch depressed the crust in that region 

 and upheaved the mighty mountain ranges to which I 

 have just referred. " 



The book bristles with cataclysms and catastrophes. 

 The shifting of a thin crust on an internal nucleus which 

 it does not fit, and incessant protrusions of granite, are 

 invoked to account for phenomena which every-day 

 people still persist in thinking are satisfactorily explained 

 by every-day causes. But the author is one born out 

 of due time — two centuries too late. How he and Burnet 

 would have enjoyed a crack together ! But there is this 

 to be said, the " Sacred Theory of the Earth" is Burnet's 

 own : the staple of the present work consists of extracts 

 from the works of others. The mottoes are verses from 

 the first chapter of Genesis, but their relevancy to the 

 subject-matter of the chapters which they head is not 

 obvious. A. H. G. 



Through Atolls and Islands in the Great South Sea. 

 By F. J. Moss. (London: Sampson Low, 1889.) 



Mr. Moss — a member of the House of Representatives, 

 New Zealand — started from Auckland, in September 1886, 

 in the schooner Buster, for a voyage among the islands 

 and islets of " the outer lagoon world." He was absent 

 seven months, and during that period he crossed the 

 equator six times, and visited more than forty islands 

 among the least frequented groups. In the present 



volume he sums up the impressions produced upon him 

 by what he saw and heard in the course of his voyage. 

 Mr. Moss, in dealing with matters which really interest 

 him, shows that he is an accurate observer and a man 

 of sound judgment. His style, although plain and 

 unpretending, is well fitted for the task he has fulfilled. 

 The best parts of the book are those in which he tries to 

 convey some idea of the daily life led by those natives 

 whose customs he had an opportunity of studying. He 

 appreciates warmly some aspects of the various 

 Polynesian types of character, but thinks that the people 

 are likely to degenerate rapidly, unless they can be 

 provided with a better class of native teachers than most 

 of those to whom the duty of guiding them is now 

 intrusted. What is needed, he thinks, is, that the is- 

 landers shall have in their work and in their amusements 

 freer scope for the imaginative powers with which they 

 are endowed, and the exercise of which is too often 

 foolishly discouraged. Everything Mr. Moss has to say 

 on this subject deserves the serious consideration of those 

 to whom his warnings and counsels are either directly or 

 indirectly addressed. 



LETTERS TO THE EDITOR. 



[ TTie Editor does not hold himself responsible for opinions ex- 

 pressed by his correspondents. Neither can he undertake 

 to return, or to correspond with the writers of, rejected 

 manuscripts intended for this or any other part of NATURE, 

 No notice is taken of anonymous communications. '\ 



Who Discovered the Teeth in Ornithorhynchus ? 



In Nature of November I4(p. 31), Profs. Flower and Latter 

 criticise my note which appeared the week previous (November 

 7, p. 11), concerning the discovery of teeth in the young Orni- 

 thorhynchtis. They promptly dismiss my claim that Sir Everard 

 Home discovered the teeth of the young Ornithorhynchus, by 

 stating that the structures described and figured by Sir Everard 

 are the well-known cornules of the adult animal. 



If they will take the trouble to turn to the plate cited by me — 

 namely, Plate lix. of the second volume of Home's " Lectures," 

 1814 — and will read the accompanying explanation, they will see 

 that Home was familiar with the teeth of both the young and the 

 old animal. 



For the benefit of those whc may not have access to Home's 

 "Lectures," I here reproduce outline tracings of two of his 

 finjures. Plate lix. Fig. 2, shows the teeth of the young Orni- 

 thorhynchus — the "first set," as Home says, "to show that 

 there are two grinding teeth on each side." The next figure is 

 a similar tracing from the succeeding plate in Home's " Lectures " 

 (Plate Ix.), which represents, to again use Home's words, "the 

 under jaw of the full-grown Ornithorhynchus paradoxus, to 

 show that there is only one grinder on each side." Both of 

 these figures are natural size. 



In thevface of these/a^/j-, further comment seems unnecessary. 



I admit, of course, that Home did not discover the chemical 

 composition of the teeth of the young animal — this was Poul ton's 

 discovery. C. Hart Merriam. 



Washington, D.C., November 30. 



[We do not reproduce the outlines sent, as anyone interested 

 in the subject may see the originals, not only in Home's " Com- 

 parative Anatomy," but in the Philosophical Transactions, where 

 they first appeared. — Ed. Nature.] 



I SHOULD be very sorry to deny the credit of any discovery 

 to Sir Everard Home, or anyone else, if any evidence could 

 be shown of its having been made. Of the figures cited by Dr. 

 Hart Merriam, that of the younger animal seems (as far as can be 

 judged from the roughly executed engraving, with the assistance 

 of the descriptive text) to represent the homy plates, showing 

 the hollows from which the true teeth have recently fallen ; that 

 of the old specimen, the same plates after they are fully grown, 

 and their surfaces worn down by attrition. This difference led 

 Home to conjecture that these plates were changed during the 

 growth of the animal — a view which was corrected by Owen 

 ("Comp. Anat. of Vertebrates," vol. iii. p. 272), by the statement 



