822 METHYL. 



difficulty, boiling between 104 and 122; its density is 2.237 at 

 69.8 (21 centig.) 



Fluoride of methyl, MeF ; obtained by distilling sulphate of 

 oxide of methyl with fluoride of potassium ; a colourless gas, of 

 which the density is 1186' ; water dissolves 1.5 volumes of it. 



Cyanide of methyl, MeCy ; an ethereal liquid, insoluble in 

 water. 



Sulphuret of methyl, MeS; a very limpid liquid of which the 

 odour is extremely disagreeable. Its density is 0.845 at 6'9.8, 

 and its boiling point 105.8 (41 centig.) The density of its 

 vapour is by experiment 2115, by theory 2158; its combining 

 measure 2 volumes. Sulphuret of methyl is formed, when 

 chloride of methyl is transmitted through an alcoholic solution 

 of protosulphuret of potassium, by double decomposition. 



Sulphydrate of sulphuret of methyl or methylic mercaptan is 

 obtained as a colourless liquid, lighter than water, which boils 

 at 69. 8 and acts upon oxides of mercury and lead like sulph- 

 hydrate of sulphuret of ethyl (Gregory). 



OXYGEN SALTS OF METHYL. 



The salts of oxide of methyl correspond so closely with those 

 of ethyl that knowing the history of one class it is easy to 

 predict the properties of the other. Anhydrous metallic oxides 

 do not alter them, while the hydrated alkalies disengage hydrate 

 of oxide of methyl from them with great facility. 



Neutral sulphate of oxide of methyl, MeO, SO 3 . This member 

 of the methyl series, which has no analogue in the ethyl series, 

 is formed when oxide of methyl and anhydrous sulphuric acid 

 are brought into contact. It constantly appears also when 

 hydrate of oxide of methyl is distilled with sulphuric acid, and 

 in larger quantity the greater the proportion of sulphuric acid 

 employed. To prepare sulphate of methyl it is convenient to 

 distil 1 part of hydrate of oxide of methyl with 8 or 1 parts 

 of sulphuric acid. When purified by washing with water, and 

 two successive distillations with chloride of calcium and quick- 

 lime, sulphate of methyl is a colourless liquid of an alliaceous 

 odour, of density 1.324 at 7l.6 (22 centig.), which boils at 

 370.4 (188 centig.), and may be distilled without change. The 

 density of its vapour is 4363.4; it is composed of equal volumes 



