300 Notices respecting New Books. 



this gas, and one in volume of oxygen, are acted upon by 

 an electric spark, over mercury, ihey inflame, and there re- 

 sult exactly two volumes of carbonic acid gas ; there is no 

 other product, and the weight of the carbonic acid gas ex- 

 actly equals the weight of the carbonic oxide and the oxy- 

 gen gas : so it is evident, that the carbonic oxide contains 

 exactly half as much oxygen as carbonic acid^ that is, 5.7 of 

 charcoal require 7.3 of oxygen to become carbonic oxide. 

 Again, this is proved by decomposition : if electrical sparks 

 be passed through carbonic acid gas, over mercury, it ex- 

 pands, and part of it is decomposed, two volumes becoming 

 two volumes of carbonic oxide, and one volume of oxygen. 



" VVhen the salt, called nitrate of ammonia is decomposed 

 by heat, an elastic fluid is disengaged, called nitrous oxide; 

 when one volume oi this gas is nuxed with one volume of 

 hydrogen, and an electric spark is passed through the mix- 

 ture, inflanmiation takes place, water is formed, and one 

 volume of elastic matter remains, which is azote. Now, as 

 one volume of hydrogen takes half a volume of oxygen, for 

 its conversion into water, it is evident that this gas, nitrons 

 oxide, must be composed of two in volun)e of azote, and 

 one in volume of oxygen, condensed into a space equal to 

 two. 



*' There is a gas produced by the solution of copper in 

 diluted nitric acid. If a little of this gas be passed into 

 a curved glass tube over mercury, and metallic arsenic be 

 sublimed in the gas, it is gradually decomposed. A solid 

 combination of arsenic and oxygen is formed, which is found 

 (if the weight of the azote remaining be compared with 

 that of the nitrous gas) to contain half a volume of oxygen, 

 and half a volume of gas remains, which is azote. So it is 

 evident, that as azote combined with one proportion of 

 oxvgen gas, forms nitrous oxide, so com.bined with two 

 proportions, it forms nitrous gas : and one volume of nitrous 

 gas mixed over water with half a volume of oxygen, is con- 

 densed, and forms a solution of nitrous acid gas in water. 

 So that this body nust consist of azote with four propor- 

 tions of oxygen, nitrous oxide being considered as azote 

 with one proportion of oxygen ; and the quantities in these 

 bodies are always the same." 



The " mode of calculating the numbers representing the ele- 

 ments" is thus defined : — "The smallest quantity bearing a 

 definite relation to another quantity, or quantities, is always 

 the datum, whether it is the first, second, third, fourth, or 

 any other added quantity in the combination. Potassium 

 f(;rms two combinations with oxygen : 100 of potassium 



