58o 



NA TURE 



[AlRIL 20, I 89; 



the v.irious sections into which the worlcs were divided — 

 15 in number— hid, under conditions carefully specified, 

 to construct barracks for the staff" of workers. The can- 

 teen arrangements were all carefully thought out, and the 

 prices of food were re^^ulated by fixed tariffs. The sizes 

 of dormitories were prescribed ; hospitals and laundries 

 have to be provided, and all the sanitary arrangements 

 appear to be most complete. 



It was a condition of their engagement that the work- 

 people should be at least seventeen years of age, no 

 Socialists or Anarchists might be employed, and all 

 drunken and dissolute persons were liable to instant dis- 

 missal. Some of the regulations appear slightly auto- 

 cratic, but doubtless with a population of from 6000 to 

 8000 persons brought together from all parts of Germany, 

 such as was to be found on certain of the sections, it was 

 necessary to insist upon a very severe discipline. We 

 are assured by the author that hitherto these rules have 

 worked satisfactorily. A detailed account is given of the 

 four bridges required for the railway crossings, also of the 

 numerous ferries and of the massive constructions needed 

 to form the entrance-locks of the canal at either end. 

 The water-level of the canal is almost coincident with 

 that of the Baltic. So that on 340 days in the year the 

 sluices can remain open, and the lock-gates into the Elbe 

 can be opened daily at certain states of the tide ; the water 

 in the canal is to be at one uniform level throughout. 



In consequence of the advanced state of the works it 

 seems probable that the undertaking may be formally 

 opened for traffic at the period originally contemplated, in 

 the summer of 1895. Steamers will be permitted to 

 propel themselves at a mean speed of about six miles an 

 hour, and sailing vessels and barges will be towed in train 

 through the canal by steam-tugs provided for this purpose. 

 Herr Beseke presents us with most exhaustive statistics 

 showing the saving in time caused by the use of the canal 

 as contrasted with the dangerous passage round the coast 

 of Denmark, and a wreck chart of the entrance of the 

 Baltic serves as an effective object-lesson of the value to 

 navigation of this new sea-way. 



In the concluding chapters we find most ample details 

 of the volume of Baltic commerce and of the tonnage en- 

 gaged therein, both in the form of steamers and sailing 

 vessels, and excellent diagrams and charts have been 

 specially prepared by the author to render these facts 

 readily intelligible to the public. Nor does Herr Beseke 

 omit to treat of the industrial value of these works and of 

 their importance to the Fatherland, both from the military 

 and naval aspects ; in fact their political significance is 

 shown to be enormous. 



The volume contains a mass of well-digested informa- 

 tion upon an undertaking concerning which but little has 

 hitherto been heird in this country, but which is destined 

 to exert a powerful influence upon the commerce of the 

 states bordering upon the Baltic. 



OUR BOOK SHELF. 

 Laws and Properties of Matter. By R. T. Glazebrook, 



M.A., F.R.S. (London : Kegan Paul, Trench, Trubner 



and Co., 1893.) 

 This is the latest addition to the manuals on " Modern 

 Science " which are appearing under the direction of Sir 



VO. 1225, VOL. 47] 



John Lubbock. It is concerned with the meaning of the 

 terms applied to matter, and with the principal properties 

 which matter possesses, and contains chapters upon units 

 of measurement, force and motion, work and energy, the 

 forms of matter and of energy, and upon the properties of 

 solids, liquids, and gases. 



The book is an excellent introduction to the study of 

 the physical properties of substances, and meets the main 

 difficulty of the beginner by supplying him with sound 

 ideas on the ground-work of his subject. It is indeed a 

 matter for regret that there are so few similar books on 

 other branches of science. 



Although the properties discussed are almost entirely 

 mechanical or physical, the author occasionally touches 

 upon the subject matter of chemistry, and here the 

 chemical reader may perhaps be puzzled to find the term 

 "molecule" applied in cases where he has been taught to 

 use the term "atom." The molecular weights given on 

 p. 184, for example, are the ordinary atomic weights of 

 the chemist. It is impossible, however, to correctly dis- 

 cuss even such chemical phenomena as are given in the 

 book, without employing the conception of atom as well 

 as that of inolecule. Thus on p. 183 it is stated that " by 

 adding to each molecule of carbonic oxide a second 

 molecule of oxygen we get carbonic acid." This con- 

 clusion is not in harmony with Avogadro's hypothesis, for 

 carbonic oxide unites with half its volume of oxygen to 

 form carbonic acid. 



The value 411'^ is much higher than those recently 

 obtained for the critical temperature of water. On p. 19 

 "dynes in a given mass" should be "dynes in a given 

 weight." The formulas on pp. 164 and 180 are not cor- 

 rectly printed. J. W. R. 



The Partition of Africa. By J. Scott Keltie. (London : 

 Edward Stanford, 1893.) 



The author of this book does not wish it to be regarded 

 as a contribution either to the geography of Africa or to 

 the history of African exploration. His object has been 

 to present " a brief connected narrative of the remarkable 

 events which, during the last eight years, have led to the 

 partition of the bulk of Africa among certain of the powers 

 of Europe." In carrying out this purpose, Mr. Keltie 

 displays wide knowledge, sound judgment, and an ad- 

 mirable power of lucid and effective exposition. The 

 details of his narrative do not come within the scope of 

 Nature, but we may note that in his occasional references 

 to the scientific aspects of the subject he invariably gives 

 evidence of a thorough grasp of the principles which can 

 alone be of vital service in the study of geography. This 

 is especially true of a luminous and interesting chapter on 

 " the economic value of Africa." The importance of the 

 work is greatly increased by a large number of carefully- 

 selected and well-executed maps. 



Forest Tithes, atid other Studies from Nature. Wy a 

 Son of the Marshes. Edited by J. A. Owen. (London : 

 Smith, Elder, and Co., 1893.) 



By "forest tithes" are meant the quantities of food 

 secured at the expense of rural folk by wild creatures of 

 the moorlands. The subject is an attractive one, and in 

 dealing with it the author of this little volume pre- 

 sents many bright and lively sketches of animal life. 

 The essays on other subjects are in their own way not 

 less pleasant. They all display an ardent love of nature 

 and a remarkable power of minute and accurate observa- 

 tion — qualities which have won for " a Son of the 

 Marshes" a place of his own among the popular writers 

 of the day. Some of the articles have already appeared . 

 in various publications ; others are now printed for the , 

 first time. 



