254 CHEMISTRY. 



life more often than any other poison. It is much used for 

 killing rats, moles, and other troublesome animals, and 

 hence the name ratsbane which is often given to it. It 

 looks much like sugar and flour, and its taste is rather sweet. 

 The metal arsenic is crystalline, of a bright steel-gray color. 

 It is not poisonous when free from oxide. It very soon 

 tarnishes when exposed to the air, and at length becomes a 

 coarse gray powder, which is a mixture of the metal and 

 its oxide. It is sometimes sold by druggists under the 

 names of " fly -powder," "cobalt," and "mercury." This 

 is wrong, for people who buy it are not as cautious in its 

 use as they would be if they knew that it w r as arsenic. 



357. Antidotes to Arsenic. Every one ought to know 

 what to do if he chance to be with any person who has 

 taken arsenious anhydride white arsenic, as it is called. 

 He should administer at once in considerable quantities 

 the whites of eggs, or milk, or flour and water, or soap- 

 suds. These, however, are but partial antidotes, doing 

 little, if any thing, more than sheathing the membranes of 

 the stomach from the arsenic. There is only one true 

 chemical antidote to this poison ferric hydrate ; but it is 

 good for nothing unless it has been freshly prepared. Its 

 efficacy results from its forming with the arsenic a com- 

 pound which is insoluble, and therefore inactive. 



There are some sure chemical tests of the presence or ab- 

 sence of arsenic in the bodies of those who are supposed to 

 have been killed by this poison ; but such investigations 

 belong properly only to the professional chemist, and there- 

 fore are not suited to this work. 



358. Antiseptic Powers of Arsenic. When arsenious an- 

 hydride is taken as a poison and destroys life, it has a 

 marked effect in preserving the body from putrefaction. 

 This is shown in various ways. Sometimes the whole 

 body is remarkably preserved for a long time after death. 



