To secure Buried Letters from Damp.--They may be wrapped in waxed cloth or paper, if there be no fear of the ravages of insects. Lead plate is far more safe: it can be made easily enough by a traveller out of his bullets. (See "Lead.") A glass bottle (with something that insects cannot eat, such as lead-plate, sealing-wax or clay, put carefully over the cork) or an earthen jar may be used. The quill of a large feather will hold a long letter, if it is written in very small handwriting and on thin paper, and it will preserve it from the wet. After the letter has been rolled up and inserted in the quill, the open end of the latter may be squeezed flat between two stones, heated sufficiently to soften the quill (see "Horn") but not so hot as to burn it, and then, for greater security against wet, the end of the quill should be twisted tight. Wax affords another easy means of closing the quill.
Picture-writing.--A very many excellent bushrangers are unable to read, rude picture-writing is often used by them, especialy in America. The figure of a man with a spear or bow, drawn as a child would draw, stands for a savage; one with a hat or gun for a European; horses, oxen, and sheep are equally to be drawn; lines represent numbers, and arrow-heads direction. Even without more conventional symbols, a vast deal may be expressed by rude picture-writing.
Reconnoitring Barren Countries by help of Porters and Caches.--The distance to which an explorer can attain in barren countries depends on the number of days' provisions that he can carry with him. Half of his load supports him on his way out, the other half on his way home. But if he start in company with a laden porter, he may reserve his own store and supply both himself and the porter from the pack carried by the latter. When half of this is consumed, the other half may be divided into two equal portions. The one is retained by the porter who makes his way back to camp, consuming it as he goes, and the other is cached (see "Caches") for the sustenance of the traveller on his return journey. This being arranged, the traveller can start from the cache with his own load of provisions untouched, just as he would have started from the camp if he had had no porter to assist him. It is evident a process of this description might be frequently repeated; that a large party of porters might start, and by a system of successive subdivisions, they could enable the traveller to reach a position many days' journey distant from his camp, with his own load of provisions and with other food placed in a succession of caches, for the supply of his wants all the way home again. The principle by which this may be effected without waste, is to send back at each successive step the smallest detachment competent to travel alone, and to do this as soon as one half of their load of food has been consumed by the whole party. Then, the other half is to be divided into two portions; one consisting of rations to supply the detachment back to the previous cache, whence their journey home has been provided for, the other portion to be buried, to supply rations for the remainder of the party, when they shall have returned (either all together or else in separate and successive detachments) back to the previous cache, whence their journey home has also been provided for. An inspection of the Table which I annex (p. 307) makes details unnecessary. The dotted lines show how the porters who first return may be dispatched afresh as relief parties. I give, in the table, a schedule of the three most important cases. In these the regular supply of two meals per diem, and a morning and an afternoon journey, are supposed. I wrote a paper on this subject, which is published in the 'Royal Geographical Society's Proceedings,' vol. ii., to which I refer those who care to inquire further into the matter. Cases where each man or horse carries a number of rations intermediate to those specified in the Table, are, perhaps, too complicated for use without much previous practice. It would be easy for a leader to satisfy himself that he was making no mistake, and to drill his men to any one of the tabulated cases, by painting a row of sticks, 50 yards apart, to represent the successive halting-places of his intended journey, and by making his men go through a sham rehearsal of what they would severally have to do. Then each man's duties could be written down in a schedule and all possibility of mistake be avoided.