5^6 



NA TURE 



[August 8, 1907 



been comprised witliin the limits of this first single 

 volume. Not content, however, with the space the 

 observers have contrived to fill with the amplification 

 of their notes and discussions of the physiography of 

 the regions which they rapidly traversed, and of 

 which they can have acquired onlv the most super- 

 ficial knowledge, Mr. Bailey Willis is yet to inflict 

 upon us another volume of his " detailed presentation 

 of results," besides the other reports that are pro- 

 mised. 



If it is asked what have been the chief fruits of this 

 skilfully-planned foray into the Chinese empire, two 

 conspicuous features may be pointed to, on which the 

 explorers deserve to be congratulated. They have 

 materially increased our knowledge of the earliest 

 Palseozoic fauna of China, and they have brought to 

 light a remarkable band of boulder-clay, full of 

 striated stones, lying apparently at the base of the 

 Cambrian system. 



The large increase which has thus been made to the 

 known Cambrian fossils of China has been provision- 

 ally discussed by Mr. Walcott in a paper published in 

 1065, 'f ths Proceedings of the United States 

 National Museum, and will be more fully treated in 

 the third volume of the Reports of the Expedition. 

 It appears that at least forty-eight genera and 172 

 species of organisms are now known to occur in 

 Chinese Cambrian formations, the greater nymber 

 being assigned by Mr. Walcott to the middle division 

 of the system. The lower division has yielded com- 

 paratively few forms, and it does not appear that any 

 trace has been recovered of a fauna older than Cam- 

 brian. The trilobitic representation is especiallv abun- 

 dant, comprising 118 species, belonging to twenty-five 

 genera. The full details respecting this primaeval fauna 

 will be awaited with much interest. 



It would appear from the observations of Messrs. 

 Bailey Willis, and Blackwelder that Richthofen 

 perhaps over-estimated the thickness of his " Sinisches 

 System," and that the chances of the recoverv of a 

 pre-Cambrian fauna were less than had been hoped 

 for. In .Shan-tung the total thickness seems to be 

 little more than 4000 feet, of which only some 1500 

 or 1600 feet are relegated to the Cambrian system, 

 the overlying strata being referred to the next member 

 of the Geological Record. The lower Cambrian divi- 

 sion, consisting of 500 or 600 feet of shales and thin 

 limestones, rests unconformably on a set of gneisses, 

 schists, and granite, with other eruptive rocks. Mr. 

 Blackwelder made a reconnaissance, in the Liau-tung 

 peninsula, nearly along Richthofen 's route; but he 

 was unable to add anything of importance to what was 

 noted by the German explorer regarding the Cam- 

 brian rocks of that district. 



In threading the gorges of the Yang-tzi, the ex- 

 pedition at Nan-t'ou found at the base of the Palseozoic 

 series a remarkable group of sediments resting 

 unconformably on granite-gneiss, and having a total 

 thickness of about 370 feet. Above a conglomerate 

 and a series of red and white sandstones lies a mass 

 of hard green boulder-clay or till, some 200 feet thick, 

 which can be seen to dip under the Ki-sin-ling lime- 

 stone. No fossils were obtained by the travellers from 

 this boulder-clay, nor after a search for two hours 

 NO. 1971, VOL. 76] 



were any found by them in the overlying bands cf 

 limestone. But as they disinterred Lower and 

 Middle Cambrian organisms from what they regarded 

 as the same limestone within less than 100 miles from 

 Nan-t'ou, they regard it as highly probable that thi> 

 ancient boulder-clay is of early Cambrian age. 



The stones are subangular, with rounded edges and 

 well-polished and well-striated surfaces. They arc 

 of various kinds of rock, and of all sizes up to two 

 feet and a half in length, and they are huddled together 

 without order, as in ordinary boulder-clay. The speci- 

 mens represented in plate .xxxviii. might have been 

 selected as typical examples from any Pleistocen" 

 boulder-clay of Europe or America. It is hardlv 

 possible to resist the evidence that here is a true glacial 

 deposit which, whether or not intercalated at the very 

 base of the Cambrian system of China, must almost 

 certainly be of early Palaeozoic date. 



The physiographical discussions in the volume are 

 most unsatisfactory. When one reflects how difficult 

 are the problems of physiographical development, how 

 much patient research is needed into the geological 

 history of a region, how much detailed local topo- 

 graphical knowledge is absolutely essential, and how- 

 little, after all, dogmatism on the subject is permis- 

 sible, one is amazed at the confidence with which the 

 physiography of vast territories is here disposed of. 

 I It is not by surveys of fifty square miles a day that 

 these oroblems are to be solved, and it is matter for 

 I regret that such jejune attempts should be made, and 

 I should find a place in what ought to be a serious 

 contribution to science. 



TEE EXPI.ORATIOX OF TIBET. 

 Tibet, the Mysterious. Bv Sir Thomas Holdich, 



K.C.M.G., ' K.C.I. E. Pp. ix + 356; illustrated. 



(London : Alston Rivers, Ltd., 1906.) Price 7^. 6rf. 



net. 

 " T^'HE public which concerns itself about Tibet is 

 -L a very small public indeed," savs .Sir Thomas 

 Holdich in the volume he has compiled for " The 

 Story of Exploration " series, and to this we may 

 add that public interest in that country is not likely 

 to be increased by such unsympathetic treatment 

 as the subject receives in this book. The storv 

 of geographical achievement in Tibet, and especi 

 ally of the attempts to reach the jealously guarded 

 capital of the then closed land, was for many years 

 one of the most fascinating interest, and now in the 

 light of the more precise information that has recently 

 been made available it could well afford re-telling as an 

 instructive record of great daring and tenacity of pur- 

 pose. In professing to supply such a summary, how- 

 ever, the present account is disappointing in that its 

 information is neither very trustworthy nor up-to-date. 

 The author does not appear to have any personal 

 knowledge of the countrv, nor has he made himself 

 sufficiently acquainted with what has been written 

 on the subject, with the result that his book betrays 

 frequent inaccuracies, and a lack of clear perspective 

 that is rather bewildering to the reader. The narra- 

 tive is made up for the most part of quotations from 

 the reports of the more or less illiterate native sur- 



