Science Siftings

New Zealand Tablet, Volume XXXV, Issue 20, 16 May 1907, Page 35

Science Sif tings

By 'Volt*

Spiders. Spiders are not insects, as most people think-. The spjider 'has eight legs, whereas an insect cannot have more than six. The nervous. system is constructed on a totally different basis, and so are the circulation and respiration. The eyes are different, the insects having, many cotmpiounxl eyes and tjhie spidser ntever having more tbato. eijgjht and all of them simple;. 1 Then p, spider has no separate head, the head and the thorax being fused together. The Mineral Jade. Most people have probably seen jade ornaments without having a very clear idea of the material of which such things are composed. Jade is -an exceedingly~tough but beautiful mineral, much of which is found in China, it is of five colors, the most highly prized jade being the white, yellow, and green varieties. The rarest of all is red jade, but this is so scarce that it has no place in market valuations. The mineral is frequently found in the beds of streams, and in searching for it Mohammedans are generally employed, as it is believed that pjeople of this faith are sensitive to its presence, and, like the water finders, are affected with shuddering fits when passing over a place where jade is to be found. The Banana. The banana was named musa after Antonius the freedman and physician of the great Augustus of the Romans, says Linnaeus. The sapientum—the wiseness— in its 'name is a graceful tribute to it as the ' wise man's food,' for, incredible as it may seem, it is perhaos the best food product of the earth, being far more productive than either wheat or potatoes, the staple food of other nations. Long ago it was calculated that it is 133 times as productive as wheat and 44 times as productive as the potato— in other words, that <bhe ground th a t would give 33 pounds of wheat or 99 pounds of potatoes would, so far as mere space is concerned, give 4000 pounds of bananas and with a fractional amount of the same trouble. It has been called the prince of the tropics ' because it takes the same place,- only to an even greater degree, in those hot coun>tries that wheat, lye, and barley ta>'ce in west Asia and Europe and that rice takes in India and China. ' The Navigation of the Air. o^J^i, f^^y discu3sill ff the future of aero-traffic, asks whether the new kind of locomotion is 'calculated to bring fresh, ills to th© human race, and says :- 1 ravelling by aeroplane is calculated in some directions" to be >a healthy mode of getting about from ?/i on ? - Pl :f G - ?"» vehicle will rise M°™ the impurii7oh » i lD^ ? the air of tlle sfcreets > an ' d &v ** m ay microbes The aeroplane, it- may be assumed, will lSs into ?£? n°-tn °- t be f * a gDeat h;ei S ht > yet neverttiethe SS*? 6 f gl °^ ° f . ai . r purifiea light ozone and but ?Z °1 sedim^tation. All this sounds ideal, nrisZ SfipS bßr han ?» there Will be a diminution, o fof th? n!u ma 7 u . nfav «^bly affect the .heart's action, sure is ? JXttSr I lncreas . es as the atmospheric presl £S™ V + Wltfl ? lawn b secretions are diminished, while evaporation from the skin and lungs is decided y aU gSKJ^h A eX .- rem f heigllts there are swellings of the oTLinz J2$ f g from * he n ° se > and'thee if a sense svmtX* nf ™ /• c the lees an ' d arms - " distressing 2SSST i«m-n U " tarn &ickness ma r eveil be simulated alHlei Z ? 7 acr °P lane - Doubtless, however,