Saltpetre for Tinder.—­In all cases the presence of saltpetre makes tinder burn more hotly and more fiercely; and saltpetre exists in such great quantities in the ashes of many plants (as tobacco, dill, maize, sunflower), that these can be used, just as they are, in the place of it.  Thus, if the ashes of a cigar be well rubbed into a bit of paper, they convert it into touch-paper.  So will gunpowder, for out of four parts of it, three are saltpetre; damaged gunpowder may be used for making touch-paper.  If it be an object to prepare a store of tinder, a strong solution of saltpetre in water should be obtained, and the paper, or rags, or fungus, dipped into it and hung to dry.  This solution may be made by pouring a little water on a charge of gunpowder, or on the ashes above-mentioned, which will dissolve the saltpetre out of them.  Boiling water makes a solution forty-fold stronger than ice-cold water, and about eight times stronger than water at 60 degrees Fahr.

Hair of Plants.—­The silky down of a particular willow (S. lanata) was used by the Esquimaux, with whom Dr. Kane had intercourse; and the botanist Dr. Lindley once informed me that he had happened to receive a piece of peculiarly excellent tinder that was simply the hair of a tree-fern.  The Gomuti tinder of the Eastern Archipelago is the hair of a palm.

Pith.—­Many kinds of pith are remarkable as tinders; that whence the well-known pith hats are made, is used as tinder in India.  Pieces of pith are often sewn round with thin cotton or silk, so as to form a long cord, like the cotton lamp-wick I have described above, and they are carried in tubes for the same reason.

b.  We now come to the different kinds of tinder that fall into our second division, namely, those that are too friable to bear handling.

Rags.—­Charred linen rags make the tinder that catches fire most easily, that burns most hotly when blown upon, and smoulders most slowly when left to itself, of any kind of tinder that is generally to be obtained.  In making it the rags are lighted, and when in a blaze and before they are burnt to white ashes, the flame is stifled out.  It is usual to make this kind of tinder in the box intended to hold it; but it can easily be made on the ground in the open air, by setting light to the rag, and dropping pinches of sand upon the flaming parts as soon as it is desired to quench them.  The sand is afterwards brushed away, and the tinder gently extricated.

Touch-wood is an inferior sort of tinder, but is always to be met with in woody countries.

Dry Dung.—­Dry and powdered cattle dung—­especially horse-dung—­will take a spark, but with trouble.  After it is lighted it can be kept burning with little difficulty.