126 



THE POPULAR SCIENCE MONTHLY. 



case, and wire gauze in the other, the heat 

 which is being taken out with it ; so that the 

 cold air inspired shall be raised in tempera- 

 ture before it reaches the lungs, and there- 

 by conduce to a conservation of the bodily 

 heat. Some interesting considerations bear 

 on this. Animals provided with bushy tails 

 seem to be so as a matter of correlation of 

 growth, their bodies being always provided 

 with thiclily-set and more or less soft fur. 

 " I cannot," says Mr. Tait, " find an animal 

 with a bushy tail which cannot, and does 

 not, lie curled up when asleep. I went 

 round the Zoological Gardens at Dublin on 

 a very cold morning in February, and found 

 the civet cat, and some other bushy-tailed 

 animals, coiled up with their noses buried 

 in the fur of their tails. 



" In the squirrel this use of the tail is 

 very marked, and in birds the same object 

 is accomplished by their burying their heads 

 in the down of the shoulders. Animals pro- 

 vided with bushy tails are all solitary in 

 their method of living, so far as I can find ; 

 and, therefore, an essential for their sur- 

 vival is some method by which variations 

 of temperature shall be resisted. The use 

 of the tail for this purpose is, I think, best 

 of all illustrated in the great ant-eater {Myr- 

 mecophaga juhata), in which the hairs of the 

 tail reach a very great size, and cover up 

 the animal when reposing, so that he looks 

 like a bundle of dried grass. It may also 

 serve as a protection by mimicry in this 

 case. Mr. Wallace states also that this ani- 

 mal uses its tail as an umbrella in a showe^, 

 and that the Indians divert its attention from 

 themselves by rustling the leaves in imita- 

 tion of a falling shower, and while he is 

 putting up his umbrella they kill him. Of 

 the quadrumana, the marmosets afford a 

 strikiug instance of a bushy tail as a prob- 

 able provision for protecting these delicate 

 creatures from depressions of the tempera- 

 ture." 



Remedy for Boiler Incrnstations. " Ap- 



paratine " is the name given to a substance 

 said to be effectual in preventing incrusta- 

 tion in boilers, and also useful wherever 

 gelatine and gelatine-like substances are re- 

 quired, as in sizing textile fabrics. It is a 

 colorless, transparent material, obtained by 

 treating any amylaceous substance with a 

 caustic alkali. It is best made, however, 



with potato-starch, treated with a lye of 

 caustic potash or soda. The best method 

 of preparing the apparatine is as follows : 

 16 parts of potato-starch are put into 76 

 parts of water, and kept in a state of sus- 

 pension by stirring ; then 8 parts of potash 

 or soda-lye at 25"" Baume are added, and 

 the whole thoroughly mixed. In a few sec- 

 onds the mixture suddenly clears, forming a 

 thick jelly, which must be beaten up vigor- 

 ously. It is now a colorless, transparent 

 substance, slightly alkaline in taste, but 

 odorless^ and of a stringy, glue-like consist- 

 ency. Exposed to the air, it dries slowly, 

 but without decomposing; and even when 

 heated to dryness, although it thickens and 

 swells, it continues unchanged, as when air- 

 dried. 



To prevent incrustation, the apparatine 

 may be placed in the boiler or added to the 

 feed-water in the tank ; but the best results 

 have been obtained by placing it directly in 

 the boiler. Applied to silk, woolen, and cot- 

 ton goods, it gives them a smoothness hith- 

 erto unattainable. When once, applied to 

 the goods, and become dry, it appears to be 

 virtually insoluble. Diaphanous or coarsely- 

 woven fabrics, when dressed with appara- 

 tine, are rendered stiff and rigid. It may be 

 used as a thickening in calico-printing 



NOTES. 



A CORRESPONDENT of the Scientific Amer- 

 ican states that in Minneapolis a supply of 

 water for extinguishing fires is obtained in 

 localities beyond the reach of the city wa- 

 ter-works by sinking four drive-wells at dis- 

 tances thirty feet apart, or fifteen feet from 

 a centre. The pipes (2^ inches) of the 

 four wells are brought together at the top, 

 where the suction-hose of the fire-engine is 

 attached. On trial an engine threw a con- 

 tinuous stream from a l^inch nozzle for 

 one hour. The water in the tubes was then 

 at the same height as at the beginning. 



The chaparral-hen is described by a 

 sportsman in Texas as a very pretty bird. 

 The female lays one egg, and then com- 

 mences sitting. While sitting she lays four 

 more, the first being the largest and the 

 fifth the smallest. The birds, when grown, 

 seem to be of the same size. By the time 

 the fifth egg is hatched the first is nearly 

 a full-fledged bird. The first egg is about 

 the size of a pheasant's ; the others range 

 in size between the pheasant's and the 

 quail's egg. 



