188 ANNUAL OF SCIENTIFIC DISCOVERY. 



ered the value of arsenic as a cure for ague long before it was recog- 

 nized as such by physicians. The arsenical fumes of certain works in 

 Cornwall were stated by the late Dr. Paris to have stopped the ague, 

 previously endemic there. More recently it has been stated, that the 

 arsenic eaters of Styria are peculiarly exempt from fevers and other epi- 

 demic diseases ; and in India the natives have long used arsenic as an 

 antidote to the poison of snakes. Dr. Robinson concluded by express- 

 ing a belief that these scattered observations were not only sufficient to 

 justify and necessitate further inquiries in this direction, but seemed in 

 themselves to shadow forth the outline of a great law, which might at 

 some future time be productive of immense benefit to mankind. 



PESTILENCE IN INDIA. 



The following is extracted from the Calcutta correspondence of the 

 London Times, dated April 9th, 1863: " The country of Jessore, on 

 the confines of which the Ganges loses itself in those innumerable 

 creeks which constitute the rich Sonderbund marshes, is well known as 

 the source of that cholera which in 1817 infected Lord Hastings' army, 

 and then became, for the first time, the scourge of Europe. In the 

 same country, a pestilence like the Egyptian plague, generally preceded 

 by cholera, has long been endemic, and during the last three yeajfs 

 since June, 18GO--has spread all round Calcutta and along the 

 line of the East Indian Railway to Burdwan. It has slain no less than 

 40,000 victims, or sixty per cent, of the whole population affected. By 

 dispensaries and native doctors, Government, always benevolent, in 

 vain attempted to arrest it, but in November, '62, with the last fall of 

 rain, it spent its fury. For miles whole villages are abandoned, and 

 there were none left to bury or burn the dead, whose corpses still pol- 

 lute the air. The report of Dr. Elliott, appointed to investigate the 

 epidemic, reveals horrors which even the technical language, of the 

 medical man does not modify. All is attributed to malaria, and water 

 so filled with decaying organisms that an oily scum floats on its surface. 

 A Bengalee village is always covered with the densest vegetation, for 

 the sake of privacy and fruit, and is destitute of the simplest means of 

 conservancy. Orders have gone forth for the clearance of jungle and 

 the filling up of pestilential pools, but the people are apathetic and hate 

 cleanliness, and probably the next rainy season, in June, will see a re- 

 currence of the plague, described as a remittent, congestive fever, 

 which carries off the victim in periods of from five hours to fifteen days. 

 Fortunately for the tropics, where vegetation is so dense, the great heat 

 destroys or checks malaria ; but the four months of rain are deadly." 



SOLVENT FOR SILK. 



M. Persoz, the eminent French chemist, has recently discovered 

 that when silk is exposed to the action of a neutral solution of chloride 

 of zinc (concentrated to about 60 of the areometer), it is converted 

 at first into a gummy mass, preserving the threads of the tissue, then 

 gradually changes into transparent clots, and finally becomes completely 

 dissolved. In fact, the process of solution is very similar to that of dis- 

 solving gun-cotton in alcoholized-ether. The solution of' silk in chlo- 

 ride of zinc, of the above strength, takes place gradually at ordinary 

 temperature ; but if heat is applied to the solvent, the solution is rapidly 



