After melting the mixture some fifteen or twenty times you will find it necessary to add a little water, and perhaps a small quantity of glycerine also, in order to replace that which has passed off by evaporation. Be careful not to overdo it, however, for a very slight error in the proportions of the different ingredients will render the mixture useless.
Ink you had better buy; it is cheap enough, costing only about ninepence a bottle, and can be obtained almost of any stationer. You can manufacture it yourself, of course, by making a saturated solution of one of the aniline dyes (mauveine is the most powerful), and adding a few drops of glycerine, but, so far as my own experience goes, the home-made article is never really satisfactory, and does not give nearly the number of copies yielded by that which is specially supplied. Always procure violet ink in preference to black or red. It is far more powerful, and gives better and more numerous impressions.
N.B.—If you should happen to spill some of this ink on your fingers, wash them at once, or you will not be able to remove the stain without considerable trouble.
One word in conclusion. Never put your graph away while wet. If you do, the composition will absorb the moisture, the proper proportions will be altered, and before very long you will find that the printing power of your machine will be a thing of the past.
CHAPTER XXXII.—CRYPTOGRAPH, OR CIPHER.
By a Naval Surgeon.
I do not know what first made me take to deciphering cryptograms. I do not think I have more of the Paul Pry in my nature than most of my neighbours. If, for example, I saw two lovers whispering together, or heard two people talking aloud by my side in a language which they mistakingly imagined I was not familiar with, I would put my fingers in my ears or walk right away rather than listen to a word of their secret. But seeing a letter in cipher in the ‘agony column’ of one of the dailies always appeared to me to be a kind of challenge to my ingenuity; and, at sea, I have taken the newspaper directly away to my cabin, and never raised my head from over it until I had puzzled out the cryptogram.
This would, of course, often be a work of some hours, but it passed the time away, and that itself is something to an idle sailor. Besides, there was some satisfaction in knowing that I was the only officer in the mess who could read difficult ciphers; and there was, too often, a good deal of amusement to be obtained from a perusal of these secret missives.
Thief often writes to thief, and evil-doer to evil-doer; but the letters are more often those of lover to lover, and innocent enough too—aye, and I might add ‘green’ enough, as well as innocent. Each of the two correspondents has a copy of the alphabet they write in. In this alphabet some other letter or figure is used for the real one. For example, they might put the first three letters of their mysterious alphabet thus:—