368 Notices respecting New Books. 



was strongly supported by experience he rejected Gray- 

 Lussac's law, and considered his own inaccurate observations 

 to be correct and the more exact results of the French chemist 

 to be faulty. 



Some of the results of this investigation are : — 



(1) Dalton was investigating the state of equilibrium in 

 mixed gases in the year 1801. This investigation caused him 

 to adopt the hypothesis M/S == C. 



(2) It is highly probable that the hypothesis M/S = C and 

 the observations of the proportions in which nitric oxide and 

 oxygen combine led Dalton to the invention of his atomic 

 theory. 



(3 Atomistic views caused Dalton to abandon the hypothesis 

 M/S = Gin the year 1805. 



(4) If we remember that all theories in chemistry are of a 

 provisional character, and that they are subject to changes in 

 course of time, then we cannot deny our admiration to the 

 great work of Dalton. It was he who first attempted to 

 w T eigh molecules and atoms and measure their volumes. 



XXXVII. Notices respecting Neiv Books. 



The Intellectual Rise in Electricity ; a History. By Paek Ben- 

 jamin, Ph.D., LL.B. London : Longmans, 1895. 

 r PIIE electrical properties of rubbed amber and the phenomena 

 ■*- exhibited by the lodestone have been known since the very 

 earliest historic times ; their discovery was probably coeval with 

 those of amber and lodestone. While the electrical fact remained 

 for many centuries isolated and apparently useless, the orientation 

 of suspended lodestone or of magnets derived from it soon sug- 

 gested the mariner's compass and led to important advances in 

 magnetic science, followed later by theories of attraction and repul- 

 sion. In the work before us Dr. Benjamin traces in a very inter- 

 esting manner the development of these facts and theories up till 

 the time of Franklin, when the recognition of electricity as a 

 natural force led to its being more universally studied. The 

 author has searched among the manuscripts and books of many 

 lands and all ages in order to find material for his history, and he 

 has even been assisted by the labours of those who have investi- 

 gated the ruins and records of ancient civilization in Phcenicia, 

 Egypt, and Scandinavia. Such a search necessarily occupies many 

 years, and we owe its satisfactory termination to the author's 

 patience and enthusiasm for his subject. 



A very plausible theory is put forward to account for the intro- 

 duction of the lodestone into Europe. It is supposed that the 

 inhabitants of Central Asia first became acquainted with its pro- 

 perties ; migrating eastwards as Mongols they carried the know- 

 ledge into China, and travelling north-westward as Einns and 



