32 



SCIENTIFIC NEWS. 



[July 13, 1? 



press our sorrow that men can be found to write, to 

 publish, and. we fear, to read such productions. 



The Movement of the Earth and the Length of 

 the Day. — Mathematicians have exercised their inge- 

 nuity in calculating the gradual lengthening of the day 

 inconsequence of a progressive retardation of the Earth's 

 rotation on her axis. Professor Young, in a lecture re- 

 cently delivered in Princeton, and noticed in Aslronomie, 

 argues against the data on which their calculations are 

 founded. He shows that the retarding influence of the 

 tides is compensated by the fact that the Earth gradually 

 contracts, owing to progressive refrigeration, which tends 

 to accelerate its rotation. Geological causes seem also 

 to neutralise each other reciprocally. An accumulation 

 of matter in the equatorial regions, would have the eftect 

 of retarding the motion of the Earth, and such an accu- 

 mulation is being effected by the Mississippi, which 

 conveys its deposit into the Gulf of Mexico. The rivers 

 of India also work in the same direction. But the 

 rivers of Siberia, the Mackenzie, and other rivers pro- 

 duce an opposite effect by conveying their debris to- 

 wards the pole. The Nile, La Plata, and Orinoco also 

 convey matter away from the equatorial regions, whilst 

 not a few of the longest rivers, such as those of China, 

 the Amazon, and the Congo, flow in a west-easterly 

 direction. Hence we may here fairly assume a com- 

 pensation. The accumulation of ice at the poles 

 must also compensate the loss of velocity due to the 

 tides. 



Further Observations on Mars. — The condition of 

 this planet has been made the subject of further obser- 

 vations by M. Fizeau in a communication to the Academy 

 of Sciences. It is an error to compare the condition of 

 Mars with that of our Earth. Mars is more remote from 

 the sun than are we in the proportion of three to two. 

 The heat and light which it receives from the sun are 

 about four-ninths of our allowance. Hence there is a 

 mean climate comparable to that of our polar circles. 

 Further the atmosphere of Mars is not like ours, which, 

 as every one knows, absorbs and stores up the solar 

 heat on the surface of the ground. Mars has no equato- 

 rial bands indicating the presence of clouds, that i=, of 

 watery vapour suspended in the atmosphere. It follows 

 that about two-thirds of the proportion of gases forming 

 our atmosphere, and serving as a storehouse for the heat, 

 are wanting on the surface of Mars, which is conse- 

 quently undergoing a state of glaciation. Besides, the 

 seasons of Mars are about twice the length of ours ; the 

 long summers melt the foot of the glaciers a little, but 

 the prolonged and severe winters which follow restore 

 to these colossal masses what they have lost. In short, 

 Mars is an immense glacier. M. Janssen agreed with 

 the views of M. Fizeau on the constitution of the 

 atmosphere of Mars, which he considers to be a 

 planet geologically older than our Earlh. 



The Public Health. — The Registrar-General's return 

 for the week ending June 30th shows that the deaths 

 registered during that period in twenty-eight great towns 

 of England and Wales corresponded to an annual rate of 

 15-9 per 1,000 of their aggregate population, which is 

 estimated at 9,398,273 persons in the middle of this 

 year. The six healthiest places were Brighton, Hud- 

 dersfield, Sunderland, Bristol, Birmingham, and Black- 

 burn. In London 2,289 births and 1,238 deaths were 



registered. Allowance made for increase of popula- 

 tion, the births were 446 and the deaths 261 below the 

 average numbers in the corresponding weeks of the last 

 ten years. The annual death-rate per 1,000 from all 

 causes, which had been i4'2, i4'2, and 14^5 in the pre- 

 ceding three weeks, rose last week to 15*1. In the thir- 

 teen weeks of last quarter the death-rate averaged i6 m g 

 per 1,000, which was 3-0 below the mean rate in the 

 corresponding periods of the ten years 1878-87. The 

 1,238 deaths included 20 from measles, 19 from scarlet 

 fever, 28 from diptheria, 27 from whooping-cough, 10 from 

 enteric fever, 36 from diarrhoea and dysentery, 2 from 

 cholera and choleraic diarrhoea, and not one from small- 

 pox, typhus, or any ill-defined form of continued fever ; 

 thus 142 deaths were referred to these diseases, being 

 124 below the corrected average weekly number. In 

 Greater London 3,032 births and 1,530 deaths were 

 registered, corresponding to annual rates of 28 6 and 14*4 

 per thousand of the population. In the outer ring 4 

 deaths from scarlet fever, 4 from whooping-cough, and 

 3 from diphtheria were registered. Two deaths from 

 scarlet fever occurred in Willesden sub-district and 2 

 from wooping-cough in Wimbledon lub-district. 



A German Antarctic Expedition. — The exploration 

 of the Antarctic regions is to be taken out of our hands 

 and those of Australia. It will be remembered that some 

 time ago a half-hearted proposal came from Australia 

 that the Home Government should contribute ^5,000 

 towards an Antarctic expedition, to which Australia 

 would contribute a like sum. A discouraging reply was re- 

 turned. It was represented, and rightly, that ^10,000 

 would go a very little way towards the exploration of 

 this enormous area of unknown surface ; but that it was 

 the intention of Her Majesty's Government "at a future 

 time" to take up the undertaking, and then Australia 

 would be invited to co-operate. But the few persons in 

 Australia really interested in Antarctic exploration were 

 not satisfied with this, and since then have been casting 

 about to find some means of carrying on the work inde- 

 pendently of the mother country. But so far their suc- 

 cess has not been great. By the time Her Majesty's 

 Government is ready to consider the subject the work 

 will have been done by Germany, and as in recent 

 colonial enterprises our enthusiasm will be kindled when 

 it is too late. It is intended to place in the Prussian 

 estimates a very considerable sum for an Antarctic expedi- 

 tion. A large staff of the best men obtainable will be 

 engaged, naval and scientific, and the organisation of the 

 expedition has been placed in the hands of Dr. Neumayer, 

 of the Hamburg Observatory, who is, perhaps, the 

 greatest authority living on Antartic matters. It is 

 intended, we understand, that the expedition will stay 

 out until our knowledge of this almost unknown region 

 has been substantially extended. At present it is 

 believed that within the Antarctic Circle there must be a 

 very large area of land. We know that there is a long 

 range of high mountains, and at least one great volcanic 

 peak. It will be stipulated that the members of the ex- 

 pedition shall exert themselves to their utmost to explore 

 the region, so that within a very few years we may 

 expect to have another great blank in the globe filled up, 

 and that not by the country of Ross whose Australian 

 colonies have a practical interest in the physiography of 

 the Antarctic, but by a nation whose interest in the sub- 

 ject is of a purely scientific character. The expedition, 

 we believe, will sail in a few weeks. — Times. 



