A PRIZE ESSAY. 
9 
forms hard soap. Ammonia forms neither hard ncr 
soft; it makes, with oil, a kind of ointment, used to 
rub a sore throat with, under the name of volatile 
liniment. But though there be these three alkalies, 
and two alkaline earths, I want you to fix in your 
mind, reader, that they all have common properties, 
called alkaline, and which will enable you to un¬ 
derstand their action, without more ado about their 
chemistry. 
The inflammables, or our fourth division, are sub 
phur and phosphorus; both used in making friction 
matches. The phosphorus first takes fire, by rubbing, 
and this sets the sulphur burning. Now, the smoke 
arising from these is only the sulphur and phosphorus 
united to the vital part of the common air. This 
compound of vital air, or oxygen, as it is called, and 
inflammables, forms acids, called sulphuric and phos¬ 
phoric acids. So if you burn coal, or carbon, it is well 
known you form fixed air, or carbonic acid. That is, 
by burning, the coal or carbon unites with the oxygen 
or vital part of common air, and forms carbonic acid. 
The heavy, deadly air, which arises from burning 
charcoal, has all the properties of an acid. And now 
let us see what these properties are. All acids unite 
or combine with the alkalies, alkaline earths, and the 
metals. When acids and alkalies do thus unite, they 
each lose , their distinguishing properties. They form 
a new substance, called a salt. It is very important 
you should fix well in your mind this definition of a 
salt. You are not to confine your idea of a salt to 
common salt. That is a capital example of the whole 
class. It is soda, an alkali, united to an acid, or 
chlorine; or, to speak in the terms the most intelligi¬ 
ble, to muriatic acid. So saltpetre is a salt. It is 
potash united to aqua-fortis. Yet in saltpetre you 
perceive neither potash nor aqua-fortis. These have 
united, their characters are neutralized by each other. 
They have formed a neutral salt. Our list of sub' 
1 * 
