Water may be cooled so as to be quite palatable by wrapping cloths around the vessels containing it, wetting them, and hanging them in the air, where a rapid evaporation will be produced. Some of the frontier-men use a leathern sack for carrying water: this is porous, and allows the necessary evaporation without wetting. The Arabs also use a leathern bottle, which they call _zemsemiyah_. When they are _en route_ they hang it on the shady side of a camel, where the evaporation keeps the water continually cool. No expedition should ever set out into the plains without being supplied with the means for carrying water, especially in an unknown region. If wooden kegs are used they must frequently be looked after, and soaked, in order that they may not shrink and fall to pieces. Men, in marching in a hot climate, throw off a great amount of perspiration from the skin, and require a corresponding quantity of water to supply the deficiency, and unless they get this they suffer greatly. When a party makes an expedition into a desert section, where there is a probability of finding no water, and intend to return over the same track, it is well to carry water as far as convenient, and bury it in the ground for use on the return trip. "Captain Sturt, when he explored Australia, took a tank in his cart, which burst, and, besides that, he carried casks of water. By these he was enabled to face a desert country with a success which no traveler had ever attained to. For instance, when returning homeward, the water was found to be drying up from the country on all sides of him. He was at a pool, and the next stage was 118 miles, at the end of which it was doubtful if there remained any water. It was necessary to send to reconnoitre, and to furnish the messenger with means of returning should the pool be found dry. He killed a bullock, skinned it, and, filling the skin with water (which held 150 gallons), sent it by an ox dray 30 miles, with orders to bury it and to return. Shortly after he dispatched a light one-horse cart, carrying 36 gallons of water; the horse and man were to drink at the hide and go on. Thus they had 36 gallons to supply them for a journey of 176 miles, or six days at 30 miles a day, at the close of which they would return to the ox hide--sleeping, in fact, five nights on 36 gallons of water. This a hardy, well-driven horse could do, even in the hottest climate."[2] [2] F. Galton's _Art of Travel_, p. 17 and 18. JOURNADAS. In some localities 50 or 60 miles, and even greater distances, are frequently traversed without water; these long stretches are called by the Mexicans "_journadas_," or day's journeys. There is one in New Mexico called _Journada del Muerto_, which is 78-1/2 miles in length, where, in a dry season, there is not a drop of water; yet, with proper care, this drive can be made with ox or mule teams, and without loss or injury to the animals.