218 



SCIENCE. 



[Vol. II., No. 29. 



When the native has decided to veliuquish 

 his house of ice for one of snow, or on a sledge- 

 journey has decided to go into camp, — in short, 

 is going to build an igloo, — the first thing done 

 is to get out the ' snow-testers,' with which they 

 determine the compactness, depth, and general 

 availability for building-purposes of the snow- 

 drifts. The ancient style of snow-tester, a, and 



SNOW-TESTERS, ANCIENT AND MODERN. 



those j'et used by the Esquimaux who have no 

 trading communications with the whalers and 

 explorers, is one made from reindeer-horn, about 

 the diameter of a little finger, and probabh^ 

 three feet long. One end is sharpened, and 

 the other, formed as a button about the size of 

 a quarter of a dollar, is held in the palm of the 

 hand. The modern tester, 6, is simpl3' the iron 

 rod of the seal-spear with the barb removed. 



Having halted on some lake that thej- know 

 hy certain signs has not yet frozen to the bot- 

 tom,-' the men scatter out like skirmishers 

 along the deep snow-drifts near the shore, and 

 commence prodding with their testers. Finally 

 a shout from one shows that he has been suc- 

 cessful ; and, leaving the tester sticking in the 

 snow to mark the spot, he and the others re- 

 turn to the sledges, which are then brought up, 

 and the building commences. 



It takes considerable experience, coupled 

 with good judgment, to pick out the best 

 building-site ; and, while the constant prodding 

 with the testers oftentimes looks foolish to a 

 spectator, it is no inconsiderable part of the 

 performance. Snow which looks perfect on 

 the crust ra&x be friable beyond use a few 

 inches deeper, and this the tester will reveal. 

 Soft drifting snow maj- cover a bank of splen- 

 did building-material. Again, the drift maj- be 

 freely interspersed with hidden stones and 

 bowlders, which the testers will bring to light 

 if freely used. This testing for good snow 

 generall}- occupies from ten minutes to a quar- 

 ter of an hour : but I have seen it drawn out to 

 an hour, or so long as it takes to build the igloo 

 itself; and, in fact, I have seen them compelled 

 to abandon the most favorable looking lake 

 after having skirted its whole outline, and 

 move on to the next. 



^ This is generally done by lying flat on the ice, and placing 

 tbeir eyes as close to it as the nose will allow, when some vary- 

 ing peculiarities of the ice-colore decide tbeir conjectures. 

 {To bt continued.) 



ILLUSTRA TIVE A PPA RA TUS FOR 

 ASTRONOMY. 



The accompanying figure represents an ap- 

 paratus designed for use in teaching astronora3'. 

 It is mounted so that tlie axis on whicli it 

 rotates is parallel to the earth's axis. Two 

 circles represent the equinoctial and ecliptic, 

 and on the latter is a strip of 

 wire cloth to represent the zo- 

 diac. The circles are of such 

 a size that the meshes of the 

 cloth (in this case a half-inch) 

 are one degree in size, and 

 larger meshes of five degrees 

 are made, extending to the cir- 

 , cle of the equinoctial. The northern halves of 

 the two colures help to hold all in position. 

 The lower part of these latter circles are dis- 

 pensed with, so that one may convenieutl}' 

 stand near the centre, the frame being of such 

 a height as to bring the centre nearly on a 

 level with the eye. 



It helps the beginner to obtain a clear con- 

 ception of the fundamental circles so often 

 referred to, of their actual position in the 



heavens, and their apparent diurnal- change 

 of motion. It enables him also to represent 

 the sun, moon, and planets in their correct 



