Science Sittings

New Zealand Tablet, 12 August 1909, Page 1275

Science Sittings

BY 'VOLT

The Stone Forests of Arizona.

The regions of the Little Colorado River in Arizona abound in wonderful vegetable petrifications, whole forests being found in some places which are hard as flint, but which look as if but recently stripped of their foliage. Some of these stone trees are standing just as natural as life, while others are piled across each other just like the fallen monarch of a real wood forest. Geologists say that those same trees were once covered to the depth of a thousand feet with marl, which transformed them from wood to solid rock. This marl, after the lapse of ages, washed out, leaving some of the trees standing in an upright position. The majority of them, however, are piled helter-skelter in all directions, thousands of cords being sometimes piled ujj on an acre of ground. Birds are Hard Workers. Birds can do work far harder than human beings. A pair of house martins when' nesting will feed their young once in twenty seconds — that is, each bird, male- and female, makes ninety journeys to and fro in an hour, or about 1000 a day. It must be remembered that on each journey the bird has the added work of catching the worm. Even so tiny a bird as the wren has been counted to make 110 trips to and from its nest within 430 minutes, and the prey it carried home consisted of larger, heavier, and harder to find insects than were caught by the sparrows. Among them were twenty good-sized caterpillars, ten grasshoppers, seven spiders, eleven worms, and more than one fat chrysalis. Photographing Animalcules. The cinematograph (writes Sir Ray Lankester in the Daily Telegraph) has yet to triumph over the difficulties presented by the minutest living things. It is, of course, easy to photograph with the microscope the most minute objects which are stationary and motionless, and to throw the photographs s,q_ obtained on to a screen by aid of a powerful lantern.' Photography applied to microscopes of the highest power has made visible particles, filaments, and ■lines which the eye, applied directly to the same microscope, could not detect.,-, / In the case of stationary objects £t is easy to obtain sufficient length of exposure of the photographic plate to make up for the feebleness of illumination which goes with high power magnification. A moVing object requires instantaneous exposures and proportionately intense illumination. It is surely an achievement of some distinction — still open, to the enterprise of ingenious "photographers and microscopists — to produce the first cinematograph records of the feeding of phagocytes and the almost incredible activities of animalcules/ I hope soon to Jiear that an Englishman has made the record. The Artificial Stone Age. The artificial stone age is a-coming. Although we-are-accustomed to speak of prehistoric man as belonging to -the stone age, the real»stone age is only dawning. Forestry has been declared a farce, and fenceposts are being growici by the farmers not by planting acorns, but by pouring a fliixture of cement, sand, and stone into moulds. Hollow telegraph poles of re-enforced concrete are common in France, and concrete piles are finding a wider, field of usefulness every year-. In Italy frarges and scows of re-enforced concrete are used. Fireproof buildings of the stone ' lumber ' are too plentiful to excite comment, and concrete cottages and residences bid fair to be equally numerous ere long. Enough has been accomplished with re-enforced concrete to show that ' forests will soon be as little needed for building purposes as buffaloes for carriage robes or deer for dinners.' The wonderful artificial stone called re-enforced concrete >s credited with all the essental properties of lumber save combustibility, and the want of this property is an advantage. Fire does not burn it quickly nor rot consume it slowly. It has the strength of steel, the durability of granite, and promises to surpass all present attainments in the future when the wonders wrought to-day will be tomorrow's commonplaces with the steel buried in stone. The ancient age of Btone and the present age of iron are uniting to produce the coming age of steelcrete, as the re-enforced concrete has been called.

A bright young Kaffir, just for fun, Sneezed down the barrel of a gun ; And just to see how things would go, He pressed the trigger with his toe. A basketful of his remains Was gathered from adjacent plains; And now his tribe, you may be sure, When they have colds use Woods' Peppermint Cure.