5°4 



SCIENTIFIC NEWS. 



[Nov. 1 6, 1388. 



the fields a singular effect of mirage. They perceived a 

 ship capsizing in a sea which was fearfully agitated, and 

 a large boat just leaving her. The apparition was visible 

 for about five minutes. In the beginning of August, 

 according to the Austrian papers, there was observed 

 at Vidorec, near Warasdin, an extraordinary mirage 

 in the vast plains surrounding this locality. There 

 were distinctly seen numerous divisions of infantry 

 going through evolutions at the command of a leader of 

 lofty stature. This phenomenon lasted several hours 

 during three successive days. Inquiries were made if 

 any divisions of infantry had been manoeuvring at a 

 distance, and if these evolutions had been rendered 

 visible at Vidorec by a mirage, but nothing ot the kind 

 could be ascertained. ______ 



The Municipal Laboratory in Paris. — In this useful 

 institution there have been examined and condemned in 

 1887, as unfit for human food, 165,410 kilos (the kilo 

 = 2 lbs. 3 ozs.) meat and fish ; 446,900 kilos of vege- 

 tables and fruit ; 14,500 kilos preserved fruits and fruit- 

 juices ; 123,325 kilos mushrooms and tomatoes. Whilst 

 in July, 1886, of 100 samples of beer examined, 55 

 were found sophisticated with salicylic acid, and in 

 December of the same year 7 per cent., last year the 

 proportion of adulterated samples had fallen to 3 per 

 cent. In milk there is also an improvement. In 1886, 

 23 per cent, of the samples were found to have been 

 watered, but last year only 21 per cent. The case is 

 worst with wines. Of the 7,295 samples tested, only 

 3,071 were found pure. The residue — more than one 

 half — had been either watered, " plastered," or mixed 

 with salicylic acid, colouring matters, etc. 



Refining Silver by Electricity. — According to the 

 Chronique Industrielle, the method of Moebius for refining 

 silver by electricity is being brought into extensive use. 

 It is especially suitable for the treatment of auriferous 

 silver containing about n per cent, of gold. The ex- 

 pense is about 1 1 franc per kilo. Moebius employs in 

 an ordinary electrolytic bath anodes of argentiferous 

 matter, and a thin plate of pure silver as cathode. The 

 bath is a weak solution of nitric acid at 1 per cent. The 

 anodes, which are about 1 2 millimetres in thickness, are 

 placed in muslin bags, which retain the gold, platinum, 

 peroxide of lead, and other foreign bodies contained in 

 the matter. The current employed is of 150 amperes, 

 with a difference of potential between the plates of one 

 volt. During the whole operation brushes pass and re- 

 pass over the surface of the cathode, and cause the 

 silver deposited to fall to the bottom. If the matter con- 

 tains copper, it dissolves in the nitric acid, but it is not 

 deposited upon the cathodes. 



Great Ocean Depths. — Her Majesty's surveying ship 

 Egeria, under the command of Captain P. Aldrich, R.N., 

 has, during a recent sounding cruise and search for 

 reported banks to the south of the Friendly Islands, 

 obtained two very deep soundings of 4,295 fathoms and 

 4,430 fathoms, equal to five English miles, respectively, 

 the latter in latitude 24* 37' S., longitude 175 8' W. 

 the other about twelve miles to the southward. These 

 depths are more than 1,000 fathoms greater than any 

 before obtained in the Southern Hemisphere, and are 

 only surpassed, as far as is yet known, in three spots in 

 the world — one of 4,655 fathoms off the north-east coast 



of Japan, found by the United States steamship Tusca- 

 rora; one of 4,475 fathoms south of the Ladrone 

 Islands, by the Challenger ; and one of 4,561 fathoms 

 north of Porto Rico, by the United States ship Blake. 

 Captain Aldrich's soundings were obtained with a Lucas 

 sounding machine and galvanised wire. The deeper one 

 occupied three hours, and was obtained in a considerably 

 confused sea, a specimen of the bottom being successfully 

 recovered. Temperature of the bottom, 33-7 deg. Fahr. 



Secular Depression of Land in France. — A long 

 series of observations has been carried out all over France 

 since the year 1884 for the purpose of detecting any 

 variations of level of the land. These observations have 

 been conducted by men belonging to the Genie corps 

 under specially selected officers, The result of this 

 series of observations is most important. It would 

 appear that a secular depression from south to north is 

 in progress. While on the coast of the Gulf of Lyons no 

 alteration of level has been noted, on the line between 

 Marseilles and Lille, a stretch of 820 kilometres, the 

 ground is sinking towards the north at the very serious 

 rate of three centimetres yearly. It is noteworthy that 

 the direction of the sinking is complicated ; it is about 

 three times greater towards the north-east than in the 

 direct line from south to north. The rate along the line 

 of the meridian is about one millimetre yearly on every 

 27 kilometres; whereas it is one millimetre on every 

 ten kilometres in a north-easterly direction. Should 

 this rate of depression continue, north-eastern France 

 would in the course of a few centuries encounter a 

 calamity similar to that which, at the end of the 13th 

 century, befell the Netherlands. 



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

 for the week ending November 3rd shows that the 

 deaths registered during that period in twenty-eight 

 great towns of England and Wales corresponded to an 

 annual rate of i9'6 per 1,000 of their aggregate popula- 

 tion, which is estimated at 9,398,273 persons in the 

 middle of this year. The six healthiest places were 

 Brighton, Birkenhead, Derby, Nottingham, Portsmouth, 

 and Halifax. In London 2,373 births and 1,613 deaths 

 were registered. Allowance made for increase of 

 population, the births were 534, and the deaths 27, 

 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 increased in the six preceding 

 weeks from i5 - 8 to 2i - 2, declined again last week to 

 1 9' 7. During the first five weeks of the current 

 quarter the death-rate averaged 19 '2, and was ot below 

 the mean rate in the corresponding periods of the ten 

 years 1878-87. The 1,613 deaths included 1 from small- 

 pox, 88 from measles, 24 from scarlet fever, 32 from 

 diphtheria, 19 from whooping-cough, 22 from enteric 

 fever, 34 from diarrhoea and dysentery, and not one 

 from typhus, ill-defined forms of fever, or cholera ; thus, 

 220 deaths were referred to these diseases, being 19 

 above the corrected average weekly number. In Greater 

 London 3,124 births and 2,025 deaths were registered, 

 corresponding to annual rates of 29'5 and i9 - i per 1,000 

 of the estimated population. In the outer ring 1 1 deaths 

 from measles, 10 from diphtheria, and 10 from diarrhoea 

 were registered. Measles caused 5 deaths in West 

 Ham and 2 in Leyton sub-districts ; and 2 deaths from 

 diphtheria were returned in Croydon, in Kingston, and 

 in Tottenham sub-districts. 



