SCIENCE IN SECONDARY SCHOOLS. 193 
Tue Kitcuen, 
Books are usually divided into chapters: when the story is carried to a 
certain point it is broken off and a new chapter is begun, in which some other 
set of characters is considered. It will be well to leave the study of food for 
a time and pass to the kitchen, where the stove and fender and fire irons are 
to be found. All these are made of iron and, like steel knives, must be care- 
fully looked after and kept bright. Why? Why too is so much care taken 
to paint ironwork out of doors? We use many other metals and leave them 
unpainted—at most they are tarnished, but iron rusts and spoils. What happens 
to it—what makes it rust? Water, you say—if water be dropped on the fender 
and be allowed to remain there or if knives are left wet, rust soon appears. 
You must not be hasty in your conclusions—you will soon find out if you are 
that your conclusions are often wrong. If water be the cause of rust, should 
not iron rust if corked up with water, say, in an ordinary medicine bottle? 
Get some bright iron nails (wire or French nails) and try the experiment; at 
the same time expose some nails in a saucer along with a little water—not 
enough to cover them. Scarcely any rusting takes place in the bottle, while 
outside the bottle the nails rust considerably. Why is this—what was the 
difference between the two experiments? If air were present in the one case 
and not in the other and in some way play a part, it may be possible by watching 
the air to find out if it be concerned. Shut some air up over water along with 
some wetted iron. Some of the air disappears—how much—is the amount 
definite ’—make sure by repeating the experiment several times. What is the 
remaining air like—is it unchanged air—how will you try! Think of a test. 
Have you not made a great discovery about air when you take into account 
what you had previously learnt in your experiments on burning? What will 
you call this active part of air—may it not, for the time, be called Fire air—the 
air which, in some way, gives rise to fire; or rust air, if you will? In the latter 
case, however, the name has reference to a less striking property of the air 
or gas; it is less significant though appropriate in its way. What becomes of 
the ‘ Fire air’ as the iron rusts—it changes the iron into rust, is it in the rust? 
If this be so, what must happen as the iron rusts—iron rust, when you handle 
it, seems to be a much lighter substance than iron (find its exact density as 
as that of iron), but is the rusted iron lighter or heavier than the unrusted ? 
ry! 
The result of this experiment should leave no doubt in your mind that iron 
rust is formed by the association or combination of the active gas in air with 
the iron—-that it is a compound of iron with the active gas. It is clear also, 
is it not? that in some way the water plays a part—as the rusting only takes 
place when the air and water act together—what that part is cannot be deter- 
mined at present, however. 
Probably you never suspected that the kitchen range, the fender and the 
fire irons were in any way to be associated with your food except that they 
were of use in preparing it—that they could be brought into relation with it 
through air and water cannot well have entered into your thoughts. Is not 
the lesson a very valuable one—is it not one that teaches you that no opportunity 
is to be neglected—that eyes must always be open and willing to see, willing 
also to send messages to the brain? 
Is not the formation of a substance such as iron rust from the metal iron 
very remarkable? Compare them carefully in every way you can and consider 
the nature or properties of the two substances. The one, like metals generally, 
is bright or lustrous when polished and is relatively heavy; it can be bent 
and beaten and drawn out without breaking—its strength being one reason 
why it is so useful. Rust, however, is quite unlike a metal—it has no strength 
and is easily powdered. What does it most resemble, especially when powdered ? 
Red earth, does it not? It may be best described as an earthy substance—in 
fact, in some parts of our country, in Devonshire particularly, the soil looks 
just like iron rust and red soils are frequently met with. You may have noticed 
too that burnt clay is not unlike iron rust. Burn some clay, if you have not. 
What is iron itself—is it found anywhere; if not, how is it made? It is 
1917. (a) 
