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tically pure drinking water is supplied by plants. In those parts 
of the world where a supply of drinking water is scanty or uncer- 
tain, the pi oe usually, or at least commonly, know of 
some plant which accumulates supplies of water which can be 
pilfered. ee coconut usually grows in marine districts, where 
fresh water is often unobtainable, except from the unripe fruits, 
which are full of delicious watery liquid, cool even when al 
around is disagreeably warm. Related palm-fruits are similarly 
utilized. I have stood on the tidal flats of Venezuela, with no 
fresh water supply within many miles, and filled a calabash with 
potable water from palm fruits about as large as goose-eggs. On 
the upper Madeira, where a great sandy plain provided no 
streams or springs within easy reach, the hollow stems of the 
bamboos could furnish water enough even to bathe in, without 
involving an excessive amount of labor in the collection. A re- 
sort to the hollow petioles of the traveller's palm for a supply of 
drinking water is common in the oriental tropics. Elsewhere, I 
have severed the woody stem of a tall-climbing bignoniaceous 
vine and caught potable water, which dripped freely. In the 
southwestern deserts of the United States, and in Mexico, the In- 
dians commonly secure drinking water by cutting off the tops 
of the large plants of Echinocactus, and beating up the soft and 
juicy pulp until water can be wrung out of it for drinking. The 
use of the sap of the sugar maple and that of the Mexican 
maguey, is very well known. The two last named do, it is true, 
yield juices which are sweet and more or less flavored, which 
character hone. the simplest class of modified beverages. 
their thirst-quenching properties than as edible products. Of 
such fruits the orange and the watermelon are the best known to 
us; but in various parts of the tropics there are more striking 
examples. The caju is almost wholly a sweet acidulous liquid, 
there bane the smallest amount of tissue that can possibly re- 
tain this juice. The unfermented juice of grapes and apples is of 
the same character, though expressed in quantity. Practically 
the same, though of different origin, is water flavored with fruit 
