178 
DE. E. EEANKLAND ON A NEW SEEEES OE 
From these data the specific gravity of the gas was calculated to be 1'9108 — a number 
which closely coincides with the calculated specific gravity of boric methide, which con- 
tains 1 volume of boron vapour and 3 volumes of methyl, the four volumes being con- 
densed to two. 
1 vol. Boron vapour . . . *75319 
3 vols. Methyl 3*10956 
2)3*86275 
1*93137 
Boric methide is produced from boracic ether and zincmethyl by the following 
reaction : — 
, ^4 ^5 O 2 j-p „ rCg H 3 n IT 1 
2 B C 4 Hs O 2 + 3Zn2 = 2 B H 3 + 6 ^ ^ 
IC4H5O2 tt J 
C2H3 
X 
Boracic ether. 
Zincmethyl. 
Boric methide. Ethylate 
of zinc. 
The formation of boric methide under these circumstances proves conclusively that 
the corresponding ethyl compound is formed, not by the removal of the whole of the 
oxygen from boracic ether, but by the actual substitution of the three atoms of oxygen 
in boracic acid by three atoms of ethyl, whilst boric methide is in like manner pro- 
duced by the similar substitution of methyl for oxygen, — a kind of substitution which is 
quite in harmony with the mode of formation of very numerous compounds in the 
organo-metallic family. 
Boric methide exists at ordinary temperatures as a colourless and transparent gas, 
possessing a peculiar and intolerably pungent odour, irritating the mucous membrane, 
and provoking a copious fiow of tears. Its specific gravity is 1*93137. It retains its 
gaseous condition when exposed to a cold of --16° C. ; but at 10° C., and under a 
pressure of three atmospheres, it condenses to a colourless, transparent, and very mobile 
liquid. It is very sparingly soluble in water, but very soluble in alcohol and in ether. 
In contact with atmospheric air it takes fire spontaneously, burning with a bright green 
flame, which is very fuliginous if the volume of the flame be considerable. If the gas 
issue into the air through a tube i^th of an inch in diameter, the amount of smoke 
is surprisingly great, two or three cubic inches of gas, when consumed in this way, 
filling the atmosphere of a capacious room with large comet-like flocks of carbonaceous 
matter. This curious phenomenon is probably due, in part at least, to the formation 
of a superficial coating of boracic acid, which envelopes the particles of carbon and 
prevents their combustion. Suddenly mixed with atmospheric air or oxygen, boric 
methide explodes with great violence. In contact with air, both boric methide and the 
vapour of boric ethide exhibit two distinct kinds of spontaneous combustion. Thus, 
when these bodies issue very slowly from a glass tube into the air, they burn with a 
lambent blue flame invisible in daylight, and the temperature of which is so low that a 
