SCIENTIFIC NE^A^S. 



[Jan. 6, iSSS. 



Heating Power of Carbonic Acid in contact with 

 THE SiuN. — At the meeting of the Physiological Society 

 of Berlin, on November 4th, Dr. Goldschneider discussed 

 the fact that carbonic acid gas in contact with the skin 

 produces a greater sensation of heat than air of the same 

 temperature. This action is due, not merely to its greater 

 power of absorbing heat and, of producing a determina- 

 tion of blood to the skin, but to its direct chemical action 

 on the terminals of the nerves, which are concerned in 

 producing sensations of heat. 



New Units of Length, etc. — M. de Freycinet 

 {Comptes Rendus) proposes the following units in place 

 of those of the metric system ; the unit of length is the 

 length of the velocity acquired at the end of a second of 

 mean time by a body falling freely in a vacuum at 

 Paris. This unit will be g'qS metre. The unit of volume 

 is a cube of which the side is iJq of the unit of length. 

 The unit of mass is the mass of water at 4'i'^C. con- 

 tained in the unit of volume. The unit of weight is the 

 weight of the unit of mass. The unit of force = the 

 unit of weight. 



Temperature of the Baltic. — During the cruise of 

 the steamer Holsatia, sent into the Baltic by the German 

 Fishery Association for scientific research, it was found 

 that off the island of Gottland, between Memel and the 

 Hoberg Bank, the temperature of the sea at the surface 

 was 55 degrees Fahrenheit, while 460 feefbelow the sur- 

 face it was only 3 7 '4 degrees. As this is one of the 

 deepest parts of the Baltic, it has been suggested that a 

 stream of cold water, coming from the Gulf of Bothnia 

 or the Bay of Finland, may be the cause of this great 

 variation iij temperature. — Nature. 



Electrical Transmission of Power, — The munici- 

 paMty of Geneva makes great use of the motive power 

 supplied by the river Rhone ; by means of turbines and 

 pumps they provide the town and fifteen neighbouring 

 communities with water, and furnish 145 manufacturers 

 with power varying from half-a-horse to seventy horse- 

 powers. Up to the present time hj^draulic power has 

 been supplied, but now the council is considering 

 whether it would not be better to generate electricity at 

 the source of power, as it could be taken so much more 

 easily to the buildings where it is required. 



Influence of Sleep on the Quantity of Carbonic 

 Acid ex:haled. — M. de Saint-Martin, in a paper com- 

 municated to the Paris Academy of Sciences, shows that 

 natural sleep reduces the quantity of carbonic acid gas 

 exhaled by about one-fifth, but lowers the quantity of 

 oxygen absorbed only by one-tenth. In sleep occasioned 

 by morphine the proportion of carbonic acid given off 

 sinks to one-half, and during the sleep induced by chloral 

 or chloroform to one-third of its normal value. During 

 the state of insensibility occasioned by the latter agent, 

 if sufficiently prolonged the blood becomes poor in 

 oxygen and is loaded with carbonic acid. 



Submarine Lighting. — According to Industries experi- 

 ments made at the torpedo station at Newport, U.S.A., 

 to ascertain the best way of illuminating the body of the 

 sea below and in the immediate neighbourhood of a boat, 

 have indicated a novel use for incandescent lamps. It was 



found that, by submerging incandescent lamps in the sea, 

 a very effective light could be obtained. Each lamp 

 is of 100 c.p., provided with a water-tight fitting and 

 connections, and mounted upon a pole 20 ft. long, which 

 is lowered vertically from the side of the vessel. By 

 this means the body of the water is illuminated to a 

 radius of 150 ft., though the light is not visible from a 

 distance. 



Sensitiveness of Taste. — Dr. F. P. Venables gives, in 

 the Chemical News, the results of a series of experiments, 

 on the degree of dilution at which different substances can 

 be tasted. Known weightsof the substances were dissolved 

 in water, diluted to known extents with water, and one 

 cubic centimetre of the solution was tasted by each of two 

 persons. The results were : — sugar, three ten-thousandths 

 of a gramme barelj' tasted; salt, one-thousandth barely 

 tasted ; tannin, two ten-thousandths tasted, one ten- 

 thousandth failed to taste ; hydrochloric acid, one ten- 

 thousandth barely tasted ; strychnine, one two-millionth 

 barely tasted. Thus the sensitiveness of taste must be 

 admitted as inferior to that of smell. 



Analysis of a Tear. — The principal element in the 

 composition of a tear is, as may readily be supposed, 

 water. The other elements are salt, soda, phosphate of 

 lime, phosphate of soda, and mucus, each in small pro- 

 portions. A dried tear, seen through a microscope of 

 good average power, presents a peculiar appearance. 

 The water, after evaporation, leaves behind it the, saline 

 ingredients, which amalgamate and form themselves into 

 lengthened crossed lines, and look like a number of 

 minute fish-bones. The discharge of tears from the 

 lachrymal glands is not occasional and accidental, as is 

 commonly supposed, but continuous, both day and night 

 — though less abundantly at night. 



Electrical Dissipation of Smoke. — It is said that the 

 discovery by Professor Lodge of the curious effect of 

 discharges of static electricity upon dust and vapour has 

 been taken advantage of by Mr. J. G. Lorrain in the con- 

 struction of an apparatus for the dissipation of smoke 

 resulting from the discharge of ordnance. Mr. Lorrain 

 proposed to employ an electrostatic generator, such as 

 Wimshurst's, in communication with appropriate con- 

 ductors arranged around the mouth of the gun, and as a 

 conductor he prefers a light wire lattice provided with 

 points. It is possible that such a device may be success- 

 ful, but trials on a full working scale will be necessary 

 before any definite opinion can be expressed. 



An Improved Earth Plate. — An earth plate, which, 

 according to Professor Dorn, reduces polarisation to a 

 minimum, and which, therefore, should prove of great 

 value to all observers of earth current, may be prepared 

 by placing in a hole in the ground a flat open box, made 

 of wood or cement, coated with asphalte. In this there 

 is an amalgamated zinc plate connected with insulated 

 wires leading to the surface, care being taken that the 

 joint is properly protected. An earthenware pipe rising 

 to the surface is placed upon the zinc ; the box is then 

 tightly packed with clay saturated with a concentrated 

 solution of zinc sulphate, and the hole is filled up. 

 Solid sulphate is dropped down the tube, and some of 

 the solution poured after it. The plate may be kept in 

 working order by adding a little fresh sulphate from time 

 to time. — Ekctrotech. Zeit. 



