714 



THE NATIONAL GEOGRAPHIC MAGAZINE 



not made good, thirst ensues, and ten 

 hours' lack of water may thicken the 

 tongue so that speech is impossible. 



THE BARRElv CACTUS 



The Indian and the desert traveler 

 often seek relief in the juices of plants 

 when water fails. The fruits of some of 

 the prickly-pears are slightly juicy, the 

 stems of the same plant or the great 

 trunks of the saguaro contain much sap, 

 but for the most part it is bitter, and 

 while it would save life, in extremity, yet 

 it is very unpleasant to use. 



The barrel cactus, or bisnaga (Bchino- 

 cactus), however, contains within its 

 great spiny cylinders a fair substitute for 

 good water. To get at this easily one 

 must be armed with a stout knife or an 

 ax with which to decapitate the plant, 

 which is done by cutting away a section 

 from the top. Lacking a suitable tool, the 

 thirsty traveler may burn the spines from 

 the outside of the bisnaga by applying a 

 lighted match, and then crush the top 

 with a heavy stone. This or other means 

 is taken to remove a section 6 to 8 inches 

 in thickness. Next a green stake is ob- 

 tained from some shrub or tree that is 

 free from bitter substances, and with this 

 or with the ax the white tissue of the 

 interior is pounded to a pulp and a cavity 

 that would hold two gallons is formed. 

 Squeezing the pulp between the hands 

 into this cavity will give from 3 to 6 

 pints of a drinkable Hquid that is far 

 from unpleasant and is generally a few 

 degrees cooler than the air. 



Scouting Indians have long used the 

 bisnaga, and a drink may be obtained in 

 this manner by a skilled operator in 5 to 

 10 minutes. Some travelers are inclined 

 to look with much disfavor on the liquid 



so obtained, but it has been used without 

 discomfort by members of expeditions 

 from the Desert Laboratory. That it is 

 often preferred by Indians' to fair wat'-r 

 is evinced by the fact that the Whipple 

 Expedition found the Mohaves near the 

 mouth of the Bill Williams River, in 

 1853, cooking ducks and other birds in 

 the juice of these plants by means of 

 heated stones dropped into the cavity 

 containing the pulp. 



The sap of the saguaro (Cereiis gigan- 

 teus) and of other cacti contains bitter 

 substances that :v^^z it impossible to be 

 used to allay .uirst by man, although it 

 may be given to burros. A supply is 

 usually obtained by felling the heavy 

 trunk and elevating the ends a few 

 inches above the ground, while the mid- 

 dle is allowed to sag lower over a bucket 

 or vessel that has been suitably placed in 

 a hole in the ground below. A cut is 

 made above the bucket to allow the 

 liquid to escape, while the process is has- 

 tened somewhat by building a fire under 

 the ends. 



The experiences of the expeditions 

 from the Desert Laboratory made it evi- 

 dent that a still or condenser, by which 

 even a small quantity of drinkable water 

 couid be obtained from the abundant sap 

 of these plants or from alkaline waters, 

 would greatly facilitate field-work. Af- 

 ter some experiment, one was designed 

 by Mr Godfrey Sykes, in which the cac- 

 tus pulp or liquid to be distilled is placed 

 in a boiler of pressed steel. This appa- 

 ratus is now used by the laboratory par- 

 ties while at work in the deserts. It has 

 a capacity of several gallons per day, 

 which enables a party to make an ex- 

 tended stay at a locality where the un- 

 treated water is undrinkable. 



