156 Analysis of' Scientific Books and Memoirs. 



mera Lucida, viz. a view of Monte Rosa from the Lago D'Orte; a second 

 from Turin ; a third from Vercelli ; a fourth from Gemmi ; and a fifth 

 from Rothorn. The last of the plates is a fine topographical chart of 

 Monte Rosa and its environs, on a scale of 3200 toises to a Paris inch. 

 It is finely engraved by Bonati of Milan, and is considered by Baron 

 Zach, a competent judge, as a perfect model for topographical charts. 



II. Memoirs of the Literary and Philosophical Society of Manchester. 



Second Scries, vol. iv. 



Nothing has contributed more to the advancement of science, and to 

 the diffusion of general knowledge in Great Britain, than the establish- 

 ment of Provincial Societies for literary and philosophical purposes. 

 Among these institutions, which are every year increasing in number, 

 the Society of Manchester has long held a distinguished place, and con- 

 tinues to sustain its high character, under the auspices of Mr. Dalton 

 and Dr. Henry ; — names which have long been associated with some of 

 the finest discoveries in chemical science. 



The present volume, which we propose only briefly to notice, contains 

 sixteen papers, Jive of which are literary, and eleven scientific. 



The first scientific paper is by Mr. Dalton, and is entitled, On Oil, 

 and the Gases obtained from it by Heat. As this paper was read so long 

 ago as 1820, the results which it contains have been in some measure su- 

 perseded by later observations. Mr. Dalton found that oil gas is not 

 altered by being kept two or three years over water or mercury, either by 

 itself, or in mixture with three or four times its bulk of oxygen gas. 

 He found that oil gas was highly absorbable by water, about sixty per 

 cent being absorbed. The gas expelled from the water was richer than 

 the original, or contained more superolefiant gas, both from the increase 

 of carbonic acid, and of the requisite oxygen. Mr. Dalton considers it as 

 nearly demonstrable, that oil gas is a mixture of carburetted hydrogen, 

 carbonic oxide, and hydrogen, with a greater or less portion of a gas sni 

 generis, consisting of the elements of defiant gas, united in the same 

 proportion, but differing in the number of atoms. 



In a note appended to the volume, and dated July 1 824, Mr. Dalton 

 adds the following important information on this subject : " From a 

 recent train of experiments, I found that the heat from the combustion 

 of those gases is accurately, or very nearly, in proportion to the oxygen 

 consumed, and that whether the gases are diluted or not ; but the light 

 is nearly in the compound ratio of the oxygen consumed, and the density 

 of the combustible gas, when the last is nearly pure ; but if it is diluted 

 with any incombustible gas, or even with hydrogen, the diminution 

 of light is vastly greater than in proportion to the dilution. I find 

 one cubic foot of oil gas (spec. grav. 0.9) equivalent to 2 or 2^ of coal 

 gas (spec. grav. 0.6) for the purpose of illumination." Page 527. 



The next scientific paper, also by Mr. Dalton, is entitled Observations 

 in Meteorology, particularly with 7-egard to the Dew Point, or Quantity 

 of Vapour in the Atmosphere. These observations were made from 1803 

 to 1 820, on the mountains in the north of England, with the view of 



