the box, but
it would not set fire to the match. It is essential, therefore, as you
see, in the first instance, to put something on the match that the
ignited phosphorus will easily fire, and which will ignite the wood. I
will say no more about this now, as I shall have to draw your attention
to the subject in another lecture. The end of the splints are generally
scorched by contact with a hot plate before they are dipped in the
paraffin, after which the phosphorus composition is applied to the
match. This composition is simply a mixture of phosphorus, glue, and
chlorate of potash. The composition is spread upon a warm plate, and the
matches dipped on the plate, so that a small quantity of the phosphorus
mixture may adhere to the tip of the match. Every match passes through
about seventeen people's hands before it is finished. I told you that in
England we generally use chlorate of potash in the preparation of the
phosphorus composition, whilst abroad nitrate of potash is usually
employed. You know that when we strike a light with an English match a
slight snap results, which is due to the chlorate of potash in the
match. In the case of nitrate of potash no such snapping noise occurs.
Some people are wicked enough to call them "thieves' matches." Just let
me show you (in passing) how a mixture of chlorate of potash and sulphur
explodes when I strike it.

[Illustration: Fig. 11.]

Now, then, comes a very remarkable story to which I desire to draw your
attention. There were many disadvantages in the use of this yellow
phosphorus. First of all, it is a poisonous substance; and what is more,
the vapour of the phosphorus was liable to affect the workpeople engaged
in the manufacture of lucifer matches with a bad disease of the jaw, and
which was practically, I am afraid, incurable. A very great chemist,
Schroetter, discovered that phosphorus existed under another form, some
of which I have here. This, which is of a red colour, was found to be
exactly the same chemical substance as the yellow phosphorus, but
possessing in many respects different properties. For instance, you see
I keep this yellow phosphorus under water; I don't keep the red
phosphorus in water. Amongst other peculiarities it was found that red
phosphorus was not a poison, whilst the yellow phosphorus was, as I told
you, very poisonous indeed. About two to three grains of yellow
phosphorus is sufficient to poison an adult. I have known several cases
of ch