;64 



NA rURE 



[August 20, 1896 



units he has been introduced to, is it safe to bring 

 another under his notice. 



Many interesting cases of motion are well expounded 

 and illustrated by diagrams, for example the motion of 

 a pendulum with a gyrostat in its bob (a case of great 

 importance in other branches of physics), and the pre- 

 cession of the equinoxes. 



The statics and kinetics of fluids are next dealt with, 

 and, as was to be expected, fluid motion is well attended 

 to. Wave motion of a fluid and the principle of Huyghens 

 are here discussed and well illustrated graphically. Then 

 follows a wonderfully complete account, for the space 

 devoted to it, of molecular phenomena of solids and 

 fluids, including a sketch of the kinetic theory of gases. 



The second half of the book, which deals with acoustics 

 and optics, we have not space to speak of in any detail. 

 Throughout we have clear description of phenomena, 

 of apparatus, and of experimental processes, always with 

 neat and truthfully-drawn diagrams. There is necessarily 

 very little in the way of mathematical exposition of these 

 subjects, but the results of mathematical and experi- 

 mental investigation are clearly stated, and the book 

 cannot but form an exceedingly useful introduction to an 

 extended course of physical study, such as that for which 

 one of the more elaborate Lehrbiicher, which have lately 

 appeared in Germany, might form a basis. It is very 

 clearly printed, and, what is a great thing in a text-book, 

 the numerous cuts have been very well engraved and 

 printed. A. Gray. 



TRAVELS AMONG THE HA USA. 

 Hausaland, or Fifteen Hundred Miles through the 

 Central Soudan. By Charles Henry Robinson, M.A. 

 Pp. 304. Map and illustrations. (London : Sampson 

 Low, Marston, and Co., 1896.) 



MR. J. A. ROBINSON, the brother of the author of 

 the book before us, died at Lokoja on the Niger 

 in 1891, while engaged in the study of the Hausa 

 language, and in his memory the Hausa Association was 

 formed in the same year with a view to carry on the 

 work. Mr. C. H. Robinson was selected by the Associa- 

 tion as their first "Hausa Student," and he left England 

 at the end of April 1893, to make acquaintance with the 

 language, and also to learn Arabic. Instead of proceed- 

 ing directly to the land of the Hausas, the climate of 

 which at the best is very trying for Europeans, he went 

 successively to Tripoli and Tunis, where he had oppor- 

 tunities of conversing with many of the Hausa pilgrims 

 •on their way from the interior of the Sudan to Mecca, 

 and with any number of Hausa slaves. 



Equipped by preliminary training in the language, and 

 accompanied by two friends. Dr. T. J. Tonkin and Mr. 

 John Bonner, Mr. Robinson reached Lokoja, at the con- 

 fluence of the Niger and Benue, in August 1894; and, 

 after wearisome delays in obtaining carriers, set out for 

 Kano, the commercial capital of the Hausa states. They 

 travelled up the Benue to Loko, then struck northwards 

 by land through Kaffa and Zaria, and reached Kano on 

 December 23. Here the party stayed for rather more 

 than three months, engaged in diligent study, and thc-n 

 returned to the Niger and to Europe. 

 NO. 1399, VOL. 54] 



Hausaland is not a defined geographical area, but a 

 group of native states occupying the fertile region of the 

 Western Sudan between the territory of the Royal 

 Niger Company (to which they are tributary) and the 

 Sahara desert. Sokoto is the predominant state, but the 

 chief town of the Hausas is Kano, a trade-centre of such 

 importance that Mr. Robinson does not hesitate to dub 

 it the " Manchester of the Soudan." The town is de- 

 scribed in some detail, and this description is perhaps 

 the most important feature of the book, which in other 

 parts suffers from " padding," including long extracts 

 from various writers on non-essential subjects. Kano is 

 estimated to contain about 100,000 inhabitants ; it manu- 

 factures much cloth, which is largely exported, and may 

 be purchased in Alexandria, Tunis, or Lagos, so widely 

 are its qualities appreciated. The markets also contain 

 European goods, which are still, for the most part, 

 brought across the Sahara from Mediterranean ports. 

 The Hausas are born traders, and having acquired 

 Mohammedan education, are by no means to be viewed 

 as savages. They are, however, inveterate slave-traders ; 

 and Mr. Robinson is of opinion that this trade cannot be 

 seriously combated until a satisfactory currency and 

 mechanical means of transport are introduced. At 

 present slaves are the larger, and cowries the smaller, 

 units of value ; and as a slave is worth several hundred 

 thousand cowries, the carriage of his value in these 

 shells would tax the resources of any caravan. There is 

 one coin which passes current through the whole of 

 Northern Africa — perhaps the last in Europe which 

 would occur to any one set to guess its nationality and 

 date — the silver Austrian thaler coined in 1780 during 

 the reign of Maria Theresa. Mr. Robinson urges a large 

 importation of these coins as a measure to promote 

 trade and discourage slavery. He has shown himself to 

 be a diligent student and a good observer, although a 

 somewhat diffuse writer, and the suggestion is worthy of 

 consideration. 



In the preface we are told that the Royal Geographical 

 Society's system of spelling place-names has been fol- 

 lowed ; but this is only done in part. The French 

 transliterations are used in some cases, and also other 

 forms — as, for example, Abutshi, Bornou, ( landja, Soudan, 

 Tchad ; where the system referred to would require — 

 Abuchai, Bornu, Ganja, Sudan, Chad. 



It is to be hoped that the efforts of the Hausa Associa- 

 tion will not be allowed to cease for want of money ; for 

 Mr. Robinson's linguistic work is of real value, and its 

 importance will appear more fully when the facsimiles 

 and translations of the Hausa MS. which he has brought 

 home, together with his dictionary and grammar of the 

 language, are published. 



OUR BOOK SHELF. 



Practical Mechanics, applied to the Requirements of 



the Sailor. By Thomas Mackenzie, Master Mariner, 



F.R.A.S., &c. Pp. xii + 175. (London : Charles 



Griffin and Co., Ltd., 1896.) 



Thi.s book is one of a very useful series on nautical 



subjects, published in order to meet a desire on the part 



of the officers of the Mercantile Marine to obtain a more 



scientific insight into the principles of their profession. 



