S86 



Notices respecting New Books. 



Both fluid compounds, when heated, are rendered solid, 

 from the expulsion of part of the ammonia. Exposure to 

 the air is attended with the same change, and the same eflTect 

 is produced by the muriatic and carbonic acid gases. 



Knowing the vohimes of the J^cid, and alkahne gases 

 which combine, it is easy to calculate the proportions of 

 each by weight in the respective salts. 



These combinations are curious in many points of view* 

 They are the first salts that have been observed liquid, at 

 the common temperature of the atmosphere, without con- 

 taining water. And they are additional facts in suport of 

 the doctrine of definite proportions, and of the relation of 

 volumes. 



LXVIII. Notices respecting New Books. 



J- HE Philosophical Transactions of the Royal Society for 

 1812, Part II. has been published since our last Number. 

 The following are its contents : 



1. Observations of a second Comet, with Remarks on it« 

 Construction. By William Herschel, LL.D. F.R.S.— 

 2. Additional Experiments on the Muriatic and Oxymu- 

 riatic Acids. By William Henry, M.D. F.R.S. V.P. of the 

 Lit. and Phil. Society, and Physician to the Infirmary, at 

 Manchester.— 3. Of the Attraction of such Solids as are 

 terminated by Planes; and of Solids of greatest Attraction. 

 By Thomas Knight, Esq. Communicated by Sir Humphry 

 Davy, Knt. LL.D. Sec. R.S. — 4. Of the Penetration of a 

 Hemisphere by an indefinite Number of equal and similar 

 Cylinders. By Thomas Knight, Esq. Communicated by 

 Sir Humphry Davy, Knt. LL.D. Sec. R.S. — 5. On the Mo- 

 tions of the Tendrils of Plants. By 'I'homas Andrew 

 Knight, Esq. F.R.S. In a Letter to the Right Hon. Sir Jo- 

 seph Banks, Bart. K.B. P.R.S.— 6. Observations on the 

 Measurement of three Degrees of the Meridian conducted in 

 England by Lieut. Col, William Mudge. By Don Joseph 

 Rodriguez. Communicated by Joseph de Mendoza Rios, 

 Esq. F.R.S.— 7. An Account of some Experiments on dif- 

 ' ferent 



