450 



SCIENTIFIC NEWS. 



[Nov. 2, ll 



sugar was used would be utterly uneatable, on account 

 of the painful effect of attempting to masticate silicious 

 particles. 



Doubtless there are some adulterations practised. I 

 have recently detected one in moist sugar, viz., common 

 salt, which is not added for its own sake, but for the 

 water which it causes to adhere to the sugar. It is not 

 added by the usual victim of the Adulteration Act, the 

 retail grocer, but by the manufacturer, and if I am not 

 mistaken, it is done by adding sea-water or brine to the 

 syrup before crystallisation. 



Falsification is more prevalent than adulteration, and 

 it is usually perpetrated on the most costly articles, such 

 as high-class wines — so called and paid for — high-priced 

 cigars, etc. Common "Italian red," diluted Catalan, and 

 other very cheap sound ordinary wines are, by skilful 

 manipulation with certain ethers and other flavouring 

 ingredients, endowed with fancy bouquets, and the rest 

 is done by a transmutation of labels according to the 

 varying demands for fancy vintages. The higher the 

 price the greater the temptation. Those who imagine 

 that by paying a high price they are secure from such 

 imposture are the most abundantly fooled. The chateaus 

 that give their names to these choice wines have usually 

 but small vineyards, producing in some cases not more 

 than two or three per cent, of the quantity of wine that 

 is labelled with their names. 



There is another kind of adulteration, of which we hear 

 very little, and which is not punishable under the Act 

 of Parliament, viz., the adulteration of silk. About 

 thirty years ago, when at the Midland Institute, I made a 

 series of experiments on aniline dyes for a leading house 

 in the silk-dyeing business. I went through the works 

 at Coventry with the head of the firm, and saw various 

 processes of " weighting" in operation. He expressed 

 his own disgust at the practice, and told me that he 

 commonly received samples of "boiled silk" (that is, the' 

 raw silk cleansed from its natural gum by boiling in 

 potash), with orders to return sixty ounces to the pound 

 when dyed. This was especially the case with black silks. 



The forty-four ounces consisted of salts of tin, lead, 

 etc., attached to the fibres by mucilaginous compounds. 

 These metallic salts become more or less crystalline when 

 the silk is dry, and cut through the modicum of actual silk 

 wherever folds occur. Ladies know all about the facts 

 of such cutting, though perhaps not of their cause. I 

 have since learned that the progress of applied science 

 has enabled the dyers now to return seventy ounces to 

 the pound. 



" China sewings," i g. f the white silk used for sewing 

 the button-holes of white waistcoats, when these were 

 fashionable, were largely loaded with acetate of lead — so 

 much so that it was easily detected by its sweet taste. 

 Sempstresses employed on such button-hole work have 

 suffered from lead colic, due to biting the ends of such 

 silk in threading their needles. 



THE RESPIRATION OF BATS DURING 

 THEIR WINTER SLEEP. 



7 we disregard the earlier investigations of Gesner 



and Buffon, Saissy was probably the first who 



examined hybernating animals. He proved that in bats 

 respiration became less frequent, and he even con- 

 jectured that in this condition they could support life in 

 an atmosphere devoid of oxygen. 



Marshall Hall examined a hybernating bat placed 

 under a glass bell. He could not determine any absorp- 

 tion of gas during an interval of ten hours, whilst the 

 same animal when awake expired in the same time 13 

 cubic centimetres of carbonic acid. Another bat con- 

 sumed in sixty hours only 10 cubic centimetres ot 

 oxygen, whilst when awake it absorbed the same 

 quantity in one hour. He found the temperature of the 

 animal higher by 2 to 3 degs. Cent, than that of the sur- 

 rounding atmosphere. According to Regnault and 

 Reiset, the marmot, in its deepest winter sleep, consumes 

 onl}' i>V of the oxygen which it would require in the 

 same time when awake. Valentin, in his numerous 

 experiments on hedgehogs and marmots, found still 

 lower values. Such animals, however, cannot bear the 

 total absence of oxygen, though they can live in an 

 atmosphere containing 10 per cent, of carbonic acid and 

 5 per cent, of oxygen. The experiments of Horwath on 

 the respiration of the pouched marmot {Spermophilns 

 citillus) led to similar results, and Voit found that the 

 marmot stores up oxygen during hybernation. 



The more recent researches of Delsaux, communicated 

 in the Naiurforscher and in the Archives de .S/c/ogvV, were 

 made on the long-eared bat (Plecotus auritus) and the- 

 common bat (J'espertilio murimis). These animals were- 

 obtained from the caverns of Maestricht, where they 

 may be found during the winter in thousands, at an 

 average temperature of 67 degs. Cent., their bodily 

 warmth being on the mean 7 '13 degs. Cent. The 

 animals were kept in the author's laboratory in the 

 dark, and at a temperature of 7 to S degs. Cent. Each 

 was kept in a separate cylinder, so that they might not 

 disturb one another. 



The respiratory rhythm during the winter sleep is 

 peculiar. In the bats sleeping in the caverns no re- 

 spiratory movement can be perceived often for a long 

 time. In the laboratory, after long intervals, which 

 may last for fifteen minutes, there occurs a series of very 

 superficial respirations. Noise and light do not affect 

 the breathing, but the slightest touch or agitation 

 occasions at once a series of respiratory movements, 

 followed, however, by long pauses of breathing if the 

 animals are not further disturbed. If the bats are aroused 

 from their sleep their temperature rises suddenly. The 

 position, whether the animal is hanging — its natural 

 attitude when asleep — or lying horizontally, seems to 

 have no effect on the breathing. If the air be exhausted 

 down to a pressure of 50 millimetres of mercury, the bat 

 suffers from asphyxia, but recovers on the re-admission 

 of air. 



A Plecotus, which had been kept for half an hour in 

 a cylinder cooled down to 21 degs. Cent., recovered and 

 breathed, although the respiratory movements had pre- 

 viously entirely ceased. Horwath had observed that 

 the hearts of hybernating animals still show regular 

 pulsations, even if their blood has cooled down to 

 + 4 degs. Cent. The animals experimented upon exhaled 

 hourly per kilogramme of their weight 57-3 to 61 milli- 

 grammes of carbonic acid at +7 '5 degs. to 8 degs. Cent., 

 but only 30/4 to 446 kilogrammes at o degs. (freezing 

 point). Thus, as in the cold-blooded animals, a reduction 

 of temperature naturally decreases the excretion of 

 carbonic acid. 



. — «^»»^»<^*tf L -* — 



Cremation. — We learn from Cosmos that cremation 

 has been formally interdicted by the Pope as a " con- 

 demnable abuse." 



