ZOOLOGY. 371 



POISONING BY LOOKING-GLASSES. 



Careful observation is beginning to reveal various sources from which 

 injury to the health may arise in quarters heretofore unsuspected. The 

 remarks upon the injurious effects of arsenical pigments have led to the 

 inquiry whether no other injurious matters have been introduced by the 

 luxuries of civilization into our atmospheres. 



Mirrors are coated with tinfoil amalgamated with mercury; this mercury 

 gradually evaporates into the atmosphere of the room, and must be received 

 (in infinitesimal quantities) into the system, and, at least, gives ground to 

 inquire what effects may arise from it. This, at least, we know, that the 

 workmen who are engaged in the manufacture of mirrors suffer severely 

 from the effects of the mercury. 



Fortunately, the day of quicksilver mirrors appears to be passing away. 

 The superiority of mirrors coated with pure silver, by Liebig's process, 

 appears to be undoubted. Metallic silver is first precipitated upon them, - 



a coat of -J-^O^Q ^ a m ^ mmeter (4^0^(1^77 f an i ncn ) is sufficient. Metal- 

 lic copper is precipitated on this to strengthen it, and varnish is applied to 

 preserve the copper from oxidation. These mirrors cost no more than those 

 made in the ordinary way, and are said to be far more beautiful. They 

 reflect twenty per cent, more light, and give the objects reflected a warm tone, 

 very different from the pale and cold tone of quicksilver mirrors. A preju- 

 dice was excited against them in consequence of some made in London and 

 Paris which did not stand well; but a manufactory at Doos, under the direc- 

 tion of a pupil of Liebig, has produced excellent mirrors, which, after a 

 period of three years, did not exhibit the least deterioration. More particular 

 information will be found in Dingler's Polytechnic Journal, Bd. CLVII. '205. 

 Communicated by M. Carey Lea. 



ATTITUDES OF THE DEAD. 



It appears that during the recent battles in Italy, some of the French phy- 

 sicians were directed by their superior medical officers, in addition to their 

 more immediate duties to the living, to study the physiological mechanism, 

 if one may so speak, of death itself, as it occurred in the battle-field; that is 

 to say, the physiognomy, positions, and attitudes incidental to death from 

 the arms of war, during, or as soon as possible after, the conflict. Thus the 

 surgeon passed from his operating ambulance to view the fallen. Is not this 

 an intensification of the moral sublime; a unique study, original, French; 

 more than tragedians ever conceived? 



Thus, Dr. Armand, physician-major of the first class, chief of the ambu- 

 lance of the head-quarters of the fourth corps of the French army of Italy, 

 relates from personal observation some interesting particulars concerning the 

 aspects and attitu !cs of the slain in the battle-fields of the Crimea and of 

 Italy, a condensed translation or sketch of which (from Gaz. Hebdom. de 

 Me'd. Sep. 16, 18-30) will be subjoined, as worthy of consideration, psychi- 

 cally, physiologically, and traumatically. 



During the day of the battle of Magenta, including the night, eight 

 hundred wounded Frenchmen and Austrians underwent capiial or minor 

 opera 1 ions and dressings at the ambulance of Dr. Armand. With his two 

 assistants, he had completed his work by the dawn of the following day, 



