Tents were devised long before the dawn of history, and they still are used as portable dwellings by men of all races and in all climes. Every year sees countless campers busy with new contrivances in canvas or other tent materials, seeking improvements— and still the prehistoric patterns hold their own. Wherever caravans or armies march, or people travel by wagon, or summer vacationists take to a gipsy life, we see wall tents of house shape, or conical ones, of heavy canvas.
But for a small party traveling in rough country, with pack animals, or in light water-craft, or perchance afoot, such cumbersome affairs are out of the question.
Wherever transportation is difficult it is impera tive that the tent should be light, compact to carry, and, if you are to make camp and break camp every day or two, it must be so rigged that it can be set up easily and quickly by one or two men.
The tent should shed heavy rains and stand securely in a gale. It should keep out insects and cold draughts, yet let in plenty of pure air. If cold weather is to be encountered, either the tent should be fitted with a very portable stove, or it should be open in front and so shaped as to reflect the heat of a log fire down upon the occupants, yet not smother them with smoke. All of which is easily said, but harder to combine in fact. Hence the multitude of tent patterns.
In designing a light tent we begin by cutting down the size to what will " sleep " the occupants and their personal duffle. Since the party is to be out of doors all day, save in uncommonly bad weather, a small tent will suffice. Then we dispense with a fly, and make the tent of waterproof material, not only to shed rain but also because plain canvas is very heavy when wet. If the journey is through a well wooded country, no poles or stakes are carried: they are to be cut on the spot. If, however, saplings are scarce in the land, then the tent is made to set up with only one pole, and this pole may be jointed; no guy stakes are used, and the pegs are light things made of steel, as few as practicable.
Tents that are to be carried on pack animals need to be of strong, heavy duck, or else carried in stout bags; otherwise they will be ruined by the sawing of lash ropes and snagging or rubbing against trees and rocks. For such work the best of army duck is none too good.
Otherwise the most suitable material is very closely woven stuff" made from Sea Island or Egyptian cotton, which has a long and strong fiber. A thin cloth of this kind is stout enough for most purposes, yet very light, and a tent made from it rolls up into a much smaller bundle than one of duck. It comes in various weights and fineness of texture. The standard grade of " balloon silk " runs about 3 1/2 oz. to the square yard in plain goods, and 5 1/2 oz. when waterproofed with paraffine. This trade name, by the way, is an absurdity: the stuff has no thread of silk in it, and the only ballooning it ever does is when a wind gets under it.
Cheaper goods, of coarser weave, and intermediate in weight between this and duck, do well enough for easy trips, if waterproofed.
These may be classed under two heads: (A) cloth filled with paraffine or other water-shedding substance; (b) cioth chemically treated so that each fiber or thread is itself repellant of water, but the interstices are left open.
In the first instance it is not practicable to treat the cloth before making it up; the wdiole tent should be soaked in a waterproofing mixture, or the " wax " ironed in, thus insuring that the seams are tight. Paraffine is used either plain (in which case it in liable to crack or flake in cold weather) or combined with some elastic substance. The " mineral wax" called ozocerite or cerasine (often used as a substitute for beeswax, and sold by dealers in crude drugs) is not so brittle as paraffine, adheres better, and, like paraffine, has no deleterious action on cloth, being chemically neutral. I have not known of it being used by tent-makers, but believe they should try it. Crude ozocerite is nearly black; when refined it is of a yellow color (cerasine) and resembles beeswax but is not so sticky. It makes a tough compound with rubber.
The plain wax process renders cloth quite waterproof, but adds considerable weight, makes the stuff rather stiff, and increases its liability to catch afire, when exposed close to a stove or camp-fire.
Cloth of class B is subdivided in two groups:
(1) Cravenetted goods, like duxbak and gabar-dine, are processed in the yarn, or by chemical treatment applied to the raw strands themselves before they are twisted into thread. Such cloth is not so waterproof as waxed or oiled stuff, yet tents made of it can be depended upon to shed rain. It is as pliable as plain cloth, not perceptibly heavier, and is not affected by changes of temperature.
(2) Willesden canvas (or twill, etc., as the case may be), also known in England as "green rot-proof," is cotton stuff soaked in an ammoniacal solution of copper that dissolves enough cellulose in the cloth to coat each fiber with a more or less impermeable " skin " of its own substance, and turns the material a light shade of green. It is not so waterproof as waxed cloth, yet sheds rain very well if the material is closely woven. What is known in this country as " green waterproof " has gone through the cupro-ammonium process and then is lightly waxed besides, making it quite waterproof but more pliable and slower burning than plain waxed stuff.
The mills produce many grades of light cloth suitable for tenting. Each tent-maker chooses for himself, and generally does his own waterproofing. In comparing samples, count the number of threads to the inch with a magnifying glass, then note weight per square yard, and strength.
Cloth proofed with linseed or other drying oil is not strong enough for tenting (for its weight) ; it is sticky in hot weather, stiff in cold, and dangerously inflammable.