SCIENCE SIFTINGS.

Auckland Star, Volume XXXVII, Issue 149, 23 June 1906, Page 10

SCIENCE SIFTINGS.

T"?EFUL SHARK SKIN. Tnousand* of sharks' skins are annually dried anrLsold. at from 12/ to 24/ | each, according to size. Drying makes ' the skins as hard and smooth as | Tr.other-o'-pearl. The material is known ias "shatrreeu." and is ianrely used for ' ! covering whip handles and rcstru—rent leases. It is also used by cabinetmakers for polishing fine woods. The fins aiv made into glue that is used very extensively by suk manufacturers, A IX)OKLNG-GLASS FOR SEA-SICK-j NESS. j A correspondent of "Nature" writes: 1 —In connection with the above subject. !it may perhaps interest your readers :to know that German sailors recommend as a cure for sea-skkness to take i a looking-glasa and look steadily at your own eyes in it. Every motion of the ship is shared by the looking-glass. ! ->nd consequently by so doing your own eyes follow the motion of the shin. SNAKES AND THEIR SENSE OF SMELL. SnaJres have a. very keea «»nse of I smell, by which-they at— kr?ery gnid;ed in the choice cl fhei.- fcoi. A mxv- | Insist has discovered that the larger i snakes at r~--s often refuse to -2t rats j captured abr• :• the bmldra-s, but ouicki'y devour those caag v -t out of doors, taken or« were kept for a day j "»- so tn a cage with au em then f.^or jA sirtilar experience ■*&$ hat with I *rraller snakes, copperheads, these declining tc eat hcase mice, letting them ran freely about the cage, or even ov=their bodies, with impunity, while field -rice were quickly disposed of. even if "bey had been dead for some little time. THE SPEZD OF FISH. Few cf us have an accurate id?a of fhe rate at which rishta rraitii. "When we say that a person is 'as fat as a oorpoise" we hardly associate a quick rate of swimninE with that indivHaa!: yet he and everybody e!se w -oul-n !ika to he able to get through the water as rspiily. Porpoises have been seen to dart round and ronnri a stealer travelling seventeen miles an hc-ar. thus prov- ! ing their capadty to swim at a greater j rate than thct. The dolphin may i« i | placed on a level with th» porpoise: but . I the bonito ha* occasionally been knowr • jto approach forty miles" for a short i j distance. Herrings in shoads move j steadily at a rate" of between ten s«.I j ;twe2—s apples. Mackerel swim muc' j faster; and both trout and salmon go jat a rapid pace when migrating up a , j stream for ■pawning. ■Whales are not | • fish m the scientific sense, but it is m- i i teresting to note that these monsters ' I swim at the rate of sixteen miles ar. ' I hour when j-crDed, although their ordi- ; i nary speed ia estimated st ;*e-r--een four {and five ~>rt** i i