APIS MELLIFICJfc. 



in water, when the oxide falls to the bottom of the vessel ; 

 white wax is known to contain tallow, when it is of a dull, 

 opaque white, and wants the transparency which distinguish- 

 es pure wax; and starch is detected by adding to the sus- 

 pected wax two per cent, of strong sulphuric acid, and then 

 washing the mixture carefully : the acid carbonizes the starch 

 without acting on the wax. 



Pure white wax is perfectly insipid, inodorous, and some- 

 what translucent. It is harder, less unctuous to the touch, 

 heavier, and less fusible than yellow wax ; its specific gravity 

 being from 0.8203 to 0.9662, and its melting point 155. It 

 melts into a colorless, transparent fluid, which concretes again 

 as it cools, resuming its former appearance. Wax is perfect- 

 ly insoluble in water, and nearly so in cold alcohol, although 

 this fluid takes up about one twentieth of its weight at a 

 boiling temperature, which, however, is again deposited as 

 the fluid cools. Ether acts in the same manner as alcohol. 

 Wax dissolves in the fixed oils, forming the base of cerates 

 and ointments, and unites in some degree, when boiled, with 

 alkalies, forming soaps. The acids at an ordinary tempera- 

 ture scarcely affect it. The products of its decomposition 

 by heat, in close vessels, show that, like the fixed oils, it is 

 a triple compound of carbon 81.607, hydrogen 13.859, and 

 oxygen 4.534, in one hundred parts. Dr. John affirms that 

 one hundred parts of wax digested in boiling alcohol is divid- 

 ed into two distinct substances, eighty parts consisting of a 

 body soluble in hot alcohol and oils, and deposited by cooling, 

 and thirteen of a substance completely insoluble in alcohol, 

 the first of which he has named cerine^ the second myridne. 



Wax is regarded as a demulcent, and is sometimes exhib- 

 ited in obstinate cases of diarrhoea and dysentery, with the 

 view of sheathing the bowels, but its place may be better 

 supplied by simple mucilages and gelatinous solutions. It 

 is generally exhibited diffused in mucilaginous fluids by 

 means of soap, in the proportion of one third part of wax, 

 with which it is first melted, and then rubbed in a mortar 

 with the fluid, which is gradually added: but Poerner's 

 method, which is first to melt the wax with olive-oil, and 

 then to mix the oily compound while hot with the mucilagi- 

 nous fluid, by triturating with the yelk of an egg, is a prefer- 

 able one. The dose is a cupful of the emulsion, containing 

 about one scruple of wax, given every four or five hours. 



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