There are times when the principle of the common step-ladder might be advantageously remembered; and a traveller who expected to have much climbing might have one of those in which a groove is run in the inside of each standard, and the rungs, working on pivots, are shut up into it, the whole forming a light and compact pole, which a man might easily carry on his shoulder. It would, however, be cheaper and better to purchase this at home than to make it abroad. A rope and batten ladder is more easily made. The rope is doubled, an eye is turned in to the bight, holes are bored in the ends of the steps or rungs, the ends of the rope are passed through, and double knots turned on to keep each step in place. A light ladder, either of this kind or that previously described, with a coil of rope to fling over the lower branches, would enable a botanist or collector of birds or insects to climb many trees otherwise inaccessible.
Fire-escapes.
In case of fire in a town, if anything—say the end of a sofa or part of a bed frame—could be projected only 1ft. or 2ft. from a window, and weighted by a chest of drawers on its inner end, it would form what persons unskilled in climbing so much require—a clear point of departure; and the blankets, sheets, and coverlets torn into strips of not less than 4in. or 6in. wide, and twisted into a two-stranded rope, could be fastened to this and used—first, to lower the more helpless persons into the street, and, finally, for the active to glide down by. It would be too much to expect, as has been proposed, that every house should have a coil of rope, but it is well to remember that if there be only a ball of string it may serve to haul up stronger lines, brought by volunteers from without. If infants are to be lowered, it is better to put them in a bag than to tie a rope round their bodies; a couple of pillow cases would be strong enough, and there would be no fear of suffocation during the minute or two of their descent. A man may tie a child on his back or descend with it in his arms, but it is much safer to lower it separately. If flames are bursting from the windows beneath, perhaps the rope may be taken to the next lower story of the opposite house so as to avoid the danger of burning the rope or scorching those who descend. Of regular fire-escapes we need say nothing, as where they are provided competent persons, very frequently seamen, are appointed to work them; but it is well to bear in mind that, as the property of flame and heated air is to ascend, a man creeping close to the floor may often traverse in safety a chamber the upper part of which is impracticable. A towel or piece of sheeting dipped in water and tied round the mouth and nose will prevent heated smoke and particles of burning matter from entering the air passages, and thus enable a person to struggle for life in situations where suffocation would be inevitable without some such expedient for its preservation.
CHAPTER VI.
TIMBER AND ITS UTILISATION.
Extraction of sap.
We have before stated that timber should never, except in cases of emergency, be felled with the sap in it; still, during the vicissitudes of rough travel, it will frequently happen that, in order to execute repairs imperatively needed, the trees must be cut down, hewn into form, and made use of at once. When this is done, the object will be to get rid of the sap which fills all the minute pores and tubes of the wood as quickly as possible. To do this, a trench, proportioned in length and depth to the quantity and size of the timber to be treated, must be dug in the earth. Lay in the logs, after denuding them of their lateral branches, fill the trench with water, and let them soak in it whilst you build a strong hard wood fire. When this is thoroughly ignited throw a number of large heavy stones into it, and as they become red hot withdraw them with twisted sticks, and throw them into the trench until the water boils actively. Continue to do this until there are a number of heated stones in the already boiling sludge; throw then a thick layer of clay, turf, and earth, over the whole mass, and leave it to steam and stew for the night. A large log, intended for the axle of a waggon or other heavy work, may be, with advantage, subjected to a second application of the same process, when it will be found much more tough and durable than if converted with the raw sap in it.
Seasoning wood.
Before proceeding to fell a growing tree for immediate use, it is well to search carefully about for a dead storm-cast trunk of the kind required, which will, as a rule, be found in tolerable condition. When a depôt is formed, or a point selected as a rendezvous, it is advisable to fell a few trees, and let them lay in store, so to speak, until they are wanted. Cutting a deep notch round the whole circumference of a tree, and letting it stand until required for use, much improves the quality of the wood. When practicable, and time will allow, it is well to leave logs of timber intended for seasoning to soak in rivers, lakes, or arms of the sea; but it is wise, at the same time, to ascertain, by the examination of pieces of wood which have fallen accidentally into the water, whether any of the creatures addicted to timber boring are found in the locality. The rivers flowing into the Black Sea abound with the Teredo navalis, or ship worm, to such an extent that floating logs very shortly become so perforated as to be perfectly useless except for firewood. Much of the timber we obtained in that part of the world was defective on account of the depredations of this pest, whose range, unfortunately, is a pretty wide one; and his works, and those of other borers, are therefore to be jealously looked for in the neighbourhood of a proposed salt or brackish water timber pond. In countries where hot springs are met with, they may be utilised for timber seasoning and other purposes. Sticks or poles intended for bending into ox bows, or other curved forms, should be placed either in boiling water or the hot embers of the camp fire until thoroughly heated through. They may then, after being properly shaped, be tied in the required form with cords, and hung in the air to dry. Several long crooked sticks may be straightened at once by forcing them side by side into the hollow of a large bamboo cane from which all the knots, except that at one end, have been removed. When a sufficient number of sticks are arranged in the cane, place it mouth upwards, and fill it to the brim with boiling water. When the first charge is cold add a second, and so on until the sticks have been about an hour in their hot bath. They can now be forced separately into smaller bamboos without water, or lashed between battens of stiff wood until cold, when such small irregularities and curves as remain may be removed by heating the part requiring treatment over the fire and carefully straightening it over the knee. Nearly all the spear handles, whether of cane or forest wood, found among wild tribes are straightened and rendered fit for use by the agency of fire. Strong and perfectly straight tubes for blow-pipes, &c., are formed by inserting a small cane into the hollow of a larger one and turning it round till any deviation from the straight line in one counteracts that of the other.