Science Siftings

New Zealand Tablet, 15 May 1913, Page 49

Science Siftings

By 'Volt.'

Mentality of Deep Sea Fish.

Fish that inhabit the depths of the sea beyond the penetration of daylight depend largely in their ? search lor prey on the senses of hearing and smell. One would think they would have no use for eyes at all; but Nature has provided some of them with organs for the emission of phosphorescent light, and in: some cases the eye itselfperforms the double service of illumination and vision. : There .is thus a feeble lighten those gloomy depths. An examination of the brains of some of these creatures made recently in Germany by Dr. Trojan shows that the conformation of : this organ, as well as ; the distribution of the nerves, favors the senses of smell and hearing. The feeble development of the optic ( lobes and nerves indicates that vision is imperfect, while the powerful olfactory and auditory nerves, the huge ' earstones,' and the size of the corresponding brain centres show what a preponderant part js played by sounds and. smells in the mental life, if such it can be called, of dwellers in the marine abysses. . ; ' Y Many Uses for Seaweed. ■,-/--' From seaweed, when reduced to ashes, are gained some r of the most beneficent preparations in use to-day. Some of these are iodine, bromine, hydriodic acid, iodides of sodium, mercury, potassium, magnesium, and calcium. From it are extracted coloring matters; volatile oil, and its ingredients are used in photography. It is further employed as coverings for flasks, in the packing of glass, china, and other brittle wares, for packing furniture, stuffing pillows and mattresses, and in upholstering. The claim is made that furniture stuffed with seaweed is kept free from moths and other insects, owing to its : salty flavor. This weed is one of the best non-conductors of heat, and finds use in thermotics, especially in the insulation of refrigerators > arid in refrigerating plants. It is also used between. walls and floors to prevent the transmission of sound. Largest Water Tank. The water supply system of Calcutta includes the largest water tank in the world. It covers an area of two and one-third acres, and the total weight when itis: full of water >is 72,000 tons. There are thirty-two miles of steel joists in the vertical columns and bracings, and in the foundations twenty miles of steel ioists and tie bars. The capacity of the tank is 9,900,0u0 gallons of water. The tank acts as a balancer and to assist the pumps when they cannot send sufficient water into the mains to meet the demand. During the night hours, when the pumps provide more water than is required, the excess quantity goes into the tank. When the demand is greater the water from the tank flows automatically into the mains. '•"•'.■ The Atmosphere. Without the atmosphere, besides the inconvenience to breathing, a great many peculiar things would be observed that would seem extraordinary to us. The sun would rise straight up in the morning into a sky as black as ebony, traverse a black sky, and sink down to rest at night into a black bed. Mo beautiful glories of the sunset and sunrise would appear, no blueness of the heavens be seen, no red sun gradually growing brighter, but one that would rise as a fiery orb and remain thus all day. No twilight nor daybreak to cheer us ; for there would be nothing to diffuse light. Unless the sun shone directly on a thing we could not see it. Thus our houses would have to be made of some transparent substance or else be artificially lighted in the daytime. No voice or .music could be heard, for there would be no medium" to carry it no bird's or insects would flit about in the trees "and above us, for there wourd be nothing to enable them to utilise their wing motion. No clouds would be seen in the intensely black sky, no thunderstorms or high winds would be possible. No vegetation could exist, and no animal could live. This, according to an authority, is the exact condition of affairs on the moon.' 11