May i8, iS88.] 



SCIENTIFIC NEWS. 



463 



^tmml 0ott$. 



Short-sightedness. — Professor Stilling, of Strass- 

 burg, concludes that there is no foundation for the 

 prevailing opinion that this affection is due to bad type, 

 bad desks, or bad light in study. 



The Severe Winter. — In consequence of the excep- 

 tionally severe weather experienced in Canada, an ice- 

 bridge was formed completely across the river, just 

 below the Niagara Falls. Several persons are said to 

 have crossed it in safety. 



Resistance of Concrete to Shell Fire. — From ex- 

 periments recently made in France it appears that cement 

 concrete offers greater resistance to shell fire than 

 armour plate, and consequently a proposal has been 

 made to face the existing casemated forts with concrete. 



Antiquarian Discovery. — This week, while some im- 

 provements were being made on the estate of Mr. A. 

 Maudslay, Twyford, near Winchester, the site and re- 

 mains of a Roman villa were discovered. The excava- 

 tion was being carefully carried on under Mr. Maudslay's 

 supervision. . 



Ni:w Minor Planet. — Minor Planet No. 277 was dis- 

 covered by M. Charlois at the Nice Observatory at 



12 h. 25 m. a.m. on May 4th, in right ascension 



13 h. 42 m. 6 sees, (decreasing 44 sees, daily), and North 

 Polar distance loi degs. 13 m. 43 sees, (decreasing 4 m. 

 daily). 



A Sanitary Blunder. — Dr. E. Verrier, writing in Le 

 Voltaire, protests against the practice of warming school- 

 rooms by means of gaseliers kept burning during the 

 daylight. This practice increases the quantity of car- 

 bonic acid in the rooms — often not efficiently ventilated 

 to begin with — fatigues the eyes, and is apt to heat the 

 heads of the scholars, whilst allowing the feet to remain 

 cold. 



Value of the Mineral Constituents of Water. — Dr. 

 N. A. Randolph mentions that minnows which throve in 

 brook-water, and remained alive in it without food lor 

 many days, died in a few hours when placed in distilled 

 water properly aerated. He holds that one of the chief 

 dietetic advantages of salads and uncooked vegetables in 

 general is that the mineral elements have not been re- 

 moved out of them. 



New Departure in Dyeing. — M. Bandsept {Le Vol- 

 taire) proposes to use, in dyeing or printing tissues, in- 

 stead of solutions, solid colours in fine powder, which are 

 to be projected against the cloth by a jet of compressed 

 air or superheated steam. If the substances used are 

 sensitive to light or to the electric current, they may be 

 decomposed or modified by these agents at the instant 

 when they are incorporated with the tissue. 



Thermic W.^ters. — According to the Londoner Zcititng, 

 after an earthquake shock at Puzzuoli, known in 

 antiquity as Forum Volcani, the four mineral springs 

 there became turbid, and rose in temperature from 144° 

 to 160" Fahr. At the distance of 300 yards from the 

 great crater, out of which fumes and sulphurous gases 



always issue, the earth opened, and steam^ was emitted 

 at the temperature of 212° Fahr. 



Spectrum of Acid Methh^emoglobine. — M. H. 

 Bertin-Sans {Comptes Rcndiis) has proved that this 

 spectrum consists of four bands ; the first very deep ; 

 the second, less marked, has about the same breadth 

 as the first. The third, intermediate in intensity 

 between the two former is about twice as broad as the 

 second. The fourth, deeper than the second or third is 

 broader than the third. 



Inorganic Evolution. — Mr. E. A. Ridsdale, in a 

 pamphlet which we hope shortly to notice at some 

 length, has introduced into the discussion of this ques- 

 tion a novel and important principle ; the " survival of 

 the most inert." That is, as the strongest affinities of 

 the elements are satisfied, the compounds which, under 

 the existing circumstances, are the most stable are formed 

 and remain, whilst instable compounds then and there 

 disappear. 



Seismometers. — Cosmos, criticising the instruments 

 used for detecting and recording earthquake shocks, and 

 showing their direction, remarks that they are not 

 respectively comparable, and are not set up in the same 

 manner. The best method of fixing such apparatus has 

 not even yet been determined. Mr. Milne, in the 

 Seistnological Ti-ansactions of Japan, makes the curious 

 observation that light objects supported on one side fall 

 more readily than such as stand free and are capable of 

 falling in all directions. 



The Royal Zoological Society of Ireland. — This 

 society, according to its report recently published, is not 

 in a satisfactory condition. The number of visitors 

 during the last year has been less by 4,500 than in the 

 year before and much lower than in any year during the 

 past ten years. The decrease in attendance is most 

 marked among the lower classes, the visitors who paid 

 two pence each for admission having fallen off by 

 upwards of five thousand, and those admitted for one 

 penny each by nearly two thousand. 



Photochromatic Properties of Chloride of Silver. 

 — This substance has the peculiar property of receiving 

 and retaining for a time the colours of incident solar 

 light. G. Staats. {Bcr. Dcntsch Chern. Gesell.)' shovis this by 

 dipping a plate of polished silver into a five per cent, 

 solution of ferric chloride. The plate at once takes a 

 slate-colour verging upon violet. In ten seconds it is 

 taken out, quickly dried with a cloth, and covered with 

 cherry-red, emerald green, orange-coloured, and blue 

 (corn-flower) glasses. In sunshine these colours appear 

 upon the plate in a few minutes. If exposed too long 

 they take a brownish cast. This interesting phenomenon 

 has not yet been explained. 



" Cold " and Incendiary Lightnings. — Julius Spiers 

 {Humboldt) has examined the behaviour of electric 

 sparks which strike along the surface of water. He 

 finds that they pass through a tenfold greater distance 

 than in dry air. Their igniting power is much increased. 

 If a charge is not strong enough it produces " cold " 

 lightning in dry air, i.e., it does not ignite combustibles. 

 But near a surface of water it produces a gliding spark 

 which ignites. This explains why lightning often 



