Science Notes.

New Zealand Mail, Issue 978, 28 November 1890, Page 7

Science Notes.

Cooking stoves are heated by electricity

I he average width of the path of destruc. tion with tornadoes it is said to be a little more than on 6 thousand feet.

The Argentine Republic sends letters in tiny boxes by electricity along wires between Buenos Ayres and Montevideo.

A good way to purify the air in a room by the production of ozone is to generate sparks from a small electrical maohine.

The light seen through the new eye piece of the Lick tslescope will be 2,000 times as bright as that seen by the naked eye.

Among the most ingenious inventions lately exhibited is a machine for drilling square, oblong, or hexagonal holes, heretofore found to be impossible.

Aluminium is Baid to answer very well for sextants, mining instruments, and other similar purposes where strength, accuracy and lightness are desirable qualities.

In an English spinning-mill the machinery pays for itself iu fourteen years, while iu all other parts of Europe it takes from twentysix to twenty-eight years.

Professor Hazen suggests that the force of a tornado may be largely diminished by the explosion of gunpowder or dynamite, just as the waterspout at sea is diverted and broken by a like disoharge of explosives.

Eating an early supper, drinking half a pint cf cold water before going to bed, and always sleeping on the right side, is warranted as a preventive for- ‘talking in his sleep’by a healthy person. 8

The journal of the Anthropological Institute contains some curious observations by Mr T. W. Shore, on the surviving signs of Celtic influence in Hampshire. In this oounty no fewer than 70 of the oldest churches tend 30 degrees north of east, instead of due east and west. Their orienta'tion is thus on the line of the old May-day sunrise, a position reverenced by the Celts.

_ Recent discoveries in Pompeii, near the Stabiana Gate, include the bodies of two men and a woman, and the trunk of a tree three metres long and 40 centimetres in diameter. Professor Pasquale identifies the tree a 3 a Lawns nobilis, and infers from the ripeness of its fruit that the eruption of Vesuvius which overwhelmed the city took place in November, and not, as is believed, in August.

Professor, Forster says that the electric deposition of dust from smoke and other sources in practice presents very groat difficulties, and is not successful unless the air to be cleared is at rest, and the walls to whioh the dust is to adhere is stioky. The dust whirls away after lighting on the surface, ana is carried off even by a very gentle stream of air. The professor’s experiments were made at the German Imperial Sanitary Department, J

The cow steam lifeboat, the Duke of Northumberland, built at Blackwall for the station at Harwich, is on the ordinary lines, but made of steel, and in fifteen water-tight compartments. The boiler and enginerooms are supplied with air by a forced draught. There is accommodation for 30 passengers abaft the engines. The vessel'is propelled by a turbine which takes in water through the bottom of the boat and discharges it by tubular orifices at the sides. Her speed is eight knots an hour ; she can be brought to in 32 seconds, and got under way in four seconds,

According to the Government Statistician of New South Wales, diamonds are found in that colony, as well as Victoria and Queensland. The principal fields in the former are situated at Bingera, near Inverell, and the mining has been fairly successful. Ud to the end of 1887, some 75,000 stones‘had been obtained, the largest weighing 55 carats or 16.2 grains. They are found in riverdrifts of the tertiary formation, and in beds derived from these. They are, harder and whiter thaa the South African stones, and on a par with those of Brazil. In 1888, the work of searching was practioally abandoned owing the severe drought.

Dr. Sohultze concludes from a long series of, experiments that beer should, not be drunk out of gla?s. The liquor, if left to stand in a glass for five minutes, even when cold and in the dark, is it seems materially affected in taste and odour. The result is due, in his opinion, to the solubility of glass m beer, and as lead is used in the mann. facture of glass, the beer becomes unwhole, some He has determined the quantity of of glass dissolved in five minutes by a cubio centimetre of beer, and the proportion of lead it contains. The figures are very small, but sufficient to show that gold-lined silver mugs, or salt-glazed stoneware jugs, are the best for holding beer.

Electrically heated flat Irons are now made whioh are very serviceable. The flat iron is of the usual form, but made hollow. The interior contains a lot of coiled wires, through which the electrical current passes and heats the wires red hot. The latter are arranged between protecting sheets of mica and asbestos. You turn a switch, Bnd the flat iron at once heats up ready or use. The street wires supply the eleetrical current. In the same way all kinds of domestio utensils may be heated, such as cake bakers, meat boilers, coffee pots, &c. Electrical platters for keeping food warm when on the table may be had. Eleotrical heaters for warming apartments are also made. There is, indeed, no end to the u«eful applications of wire and eleotrlolty.