Friedel and Crafts on the Ethers of Silicic Acid. 165 
At this moment the mercury thermometer is -—. away, ee 
. receiver is changed, and-on continuing to heat, s bundan 
colorless product passes. 72 The gsi distilled pe 
850°, was rectified with a thermometer placed in the retort; a 
very small quantity of a product, ah ge distilled below 350°, 
was collected by itself, then the thermometer was a: and 
the distillation continued, and in a few instants almost the A 
contents of the retort passed over into the receiver. It did n 
appear doubtful to me, that a body, which distills with so chee 
rapidity could be other than a definite product, having a fixed 
boiling point near 350°.” According to Ebelmen the ‘bialions 
can also be obtained by adding to the protosilicate alcohol, con- 
taining the requisite quantity of water. 
As for the quadrisilicate, he says that it is obtained by adding 
a little aqueous alcohol to the bisilicate, and remains in the re- 
tort after the distillation of the latter. It appears to be decom- 
posed into bisilicate and silica at a temperature a little above that 
at which the bisilicate distills, The existence of these two ethers, 
if we give them the formule 
Si 251 
(C,H. fs % se,H) fe ™ x6, i.) | Oe 
accords aa with what is known of the formation of con- 
densed bodies Wuriz* has observed the formation o poly- 
the formation of ‘polpactey lente compounds. nd Frie- 
delt have shown that the theory of condensations is applicable 
to acids as well as to alcohols, and severa fe congetan gee 
sults from this, that if in order to take the most aciges case, we 
take the hydrate of silicium, corresponding to the chlorid, in 
which the 4 atoms of chlorine are replaced by 4 equivalents of 
the body HO, 
6H 
( 
eH 
(1.) HOGS = "Si, 4(68). 
H 
We can derive from this hydrate, which with pene we call nor- 
mal, the following hydrates containi ing less wa 
First, without condensation : 
* Bulletin de la Société mana A f), i, 82; December, 1859. 
Répertoire de Chimie pre ii, 
t Ann. de Chim. ne wid a i 1; 1861. 
§ Comptes Rendus des Sciences, liv, 1075; 1862. 
Am. Jour. Scr.—Szconp aia Vou. epte No. 128.—Mancu, 1967. 
22 
