Illuminated Writing
It is well known that if any words are written on a wall with solid
phosphorus, the writing will appear as if on fire; but it is
necessary to give this caution, lest accidents should occur. In using
it, let a cup of water be always near you; and do not keep it more
than a minute and a half in your hand, for fear the warmth of your
hand should set it on fire. When you have written a few words with it,
put the phosphorus into the cup of water, and let it stay a little to
cool; then take it out, and write with it again.