Combinations of different Metals and Chlorine, &c. 87 

 arsenic and corrosive sublimate, or of arsenic and calomel, 

 and [)v the distil'.alion of niuriat of arsenic with concen- 

 trated' sulphuric acid. The old method by means of cor- 

 rosive sublimate appears best adapted for procuring it in a 

 pure state. About six parts of corrosive sublimate to one 

 of arsenic are, I Hi.d, proper proportions, i he mixture 

 of the two substances should be intimate, and the heat ap- 

 plied to the retort for the disliliaiiou of the tuming liquor, 

 gentle. When the liquor was not colourless at first, I have 

 purified it bv a second distillaiion. , 



The fumiiKT hquor of arsenic, it is well known, is de- 

 composed bv^water. The precipitate produced appears lo 

 be merely white oxide of arsenic : for, independent ot other 

 circumstances, it does not atTord the fuming liquor when 

 heated with stionc sulphuric acid. , ,. , i 



The fuming liq^uor, when gently heated, dissolves phos- 

 phorus, but it retains on cooling only a very small portion 

 of this substance. The warm solution is not luminous m 



The fumincr liquor also, when warm, readily dissolves 

 sulphur; indeed sulphur fused in the liquor seems capable 

 of combining or of mixing with it in all proportions; but 

 on coohng the createst part of the sulphur is deposited, and 

 assumes a fine^ crystalline appear.aice ; the form oi the 

 crystals was apparently the octahedron. This deposition 

 seems to be merely s'ulphur with a little of the tummg 

 liquor between the intei slices of the crystals ; for the crystals 

 bear washms, and become tasteless superficially, but re- 

 main still acid internaliy, where ihe water has not pene- 

 trated. , . , ,, , 



It likewise dissolves resin. That which was called rosin 

 was the subject of experiment. Tlie solution was of a 

 blueish ureen colour ; but when genilv healed it became 

 brovMi, smd remained so on coolinir. The portion of resin 

 the fumin^- liquor is capable of taking up is very cousiGer- 

 able; when the resin was added in excess, a viicid mixture 

 was formed. The resinous soluiiou was decomposed by 

 water, and the resin was separated apparently uuallered 

 mixed wiih white arsenic. _ 



The fuming liquor is capable of combining with oil ot 

 turpentine and with olive oil. When ihe mixture was 

 made with cither of these oils, there was a considerable 

 elevation of temperature, and a homogeneous col )urless 

 fluid was in each instance obiaiiud. 



In these and some other properties, the fuming liquor ot 



arsenic is analogous to the fuming compounds ot chlorine 



p 4 anu 



