Water a loose 
and inexact 
name. 
Carbon, 
Hydrogen, 
Oxygen, 
Nitrogen, 
are really 
familiar. 
Written for 
short; C, EH, 
ON: 
10 ON THE PLACE OF FISH -IN 
matter suspended or floating about in it. They of 
course really do not form part of the water any more 
than a boat floating on water does—for when left at 
rest, they settle down in the vessel containing the 
water. By careful distillation an ordinary water can 
be freed from almost all traces of matter it has 
dissolved, and the Hydrogen-Oxide is left almost pure. 
Even if the temperature is so reduced it becomes 
solid it is still Hydrogen-Oxide, though in ordinary 
language it is then called ice ; if the temperature is 
so raised that it passes to the gaseous state it is still 
Hydrogen-Oxide, though in ordinary language it is 
called vapour. Jhere are several ways in which 
Oxygen and Hydrogen can be caused to unite to 
form water, and ways in which water can be split up 
into Oxygen and Hydrogen. Just as carbonic acid 
results from the oxidation of Carbon, water results 
from the oxidation of Hydrogen. 
The name Hydrogen-Oxide is an exact name—water 
is a loose and inexact name. Every one then is quite 
familiar with Hydrogen-Oxide though they know it 
in its impure state and under the name of water, or 
other native name for it, aqua, l'eau, wasser, &c. 
When some few facts like these are mentioned 
your “first man at the corner of the street’ would no 
longer regard Carbon, Hydrogen, Oxygen and Nitro- 
gen as unknown strangers, even though their names 
may come as new. 
To those not accustomed to considering foods as 
consisting of so many ounces of Carbon, Hydrogen, 
Oxygen, and Nitrogen, generally written for short 
C, H, O, and N,* the subject may at first sight seem 
* See note in Appendix. 
