C11EMISTRY. 



MM "*" with the old. The shadM obtained are 

 nor* beautiful and solid, and the impression 1* bct- 

 rdeflned To* new Indigo-blue, requiring no *ub- 

 ng proeeae, can be prinUd along with a 



* 

 hrome color*, colon nxed with 



U.Tnna new atyle. may be created which 



tM difficult to execute in any other manner. 



The bhM printing color 1* formed by thickening 

 with nun. or any other suitable material, a sufficient- 

 ly concentrated .olution of white indigo in an alkali. 

 and adding to the mixture a ufflcient quantity of 

 hydiwnlphiu of aoda. After printing, the piecea are 

 hang up for twenty-four hours to oxidise, waahed 

 ... . . .., .. 



SUieie Altokolt. Carbon has hitherto been 

 considered the sole alcohol-forming element, 

 but Dr. Emerson Reynolds, in a discourse before 

 the English Royal Institution, has shown how 

 by chemical means flint and quartz may be 

 made to yield an alcohol, resembling in chemi- 

 cal action, and even in appearance, the alcohol 

 of wine. We meet with nearly pure carbon 

 (which is the alcohol-producing element pur 

 ixttUrnce) under the three forms of charcoal, 

 graphite, and diamond. We can easily pre- 

 pare the corresponding varieties of silicon 

 the amorphous, the graphitoid, and the ada- 

 mantine. The specific gravity of carbon is 

 lowest in charcoal and highest in diamond, 

 and corresponding differences are observed 

 between the varieties of silicon. And as the 

 specific heat of diamond is lower than that of 

 graphite, so is the specific heat of adamantine 

 silicon lower than that of the graphitoid 

 variety. The chemical relations between the 

 two elements, silicon and cnrbon, are also very 

 close. Thus charcoal and coke burn readily 

 in oxygen, while graphite is consumed with 

 le difficulty, and the diamond is still 

 more difficult of combustion ; so, too, amor- 

 phous silicon burns readily in oxygen, while 

 the graphitoid and adamantine varieties are 

 very difficult of combustion. Crystalline sili- 

 con may even be raised to a white heat in 

 oxygen without burning. 



We next pass to a compound of silicon with 

 hydrogen. It may be prepared in a pure state 

 by a rather complex reaction : but the impure 

 gas may be easily obtained by Wohler's method, 

 rli., treating a compound of silicon and mag- 

 nesium with hydrochloric acid. Wo thn- 

 oolorleM, spontaneously inflammable gas, which 

 burns with a bright light on contact with tin- 

 air. The composition* of these silicon and 

 carbon compounds are shown in this table : 

 - ", Oxides CO, 



BKJ1. Chlorides CCI, 

 <1e C.CI. 



Sill. Hydrides HI, 

 As numb-gas Cn, is the typical carbon 

 compound from which some alcoholic series 

 may be supposed to spring, and as in these 

 oas*js the carbon of the mar*h-gs In the group- 

 ing element of the compound, so the silicon in 

 8IH. (sHictaretted hydrogen) is the mu-leim 

 round which can be grouped bydroivl, im thy]. 



ethyl, etc., so as to form silicic alcohols. Sev- 

 eral" of the less complex terms are still want- 

 ing, but their existence is rendered highly 

 probable by the occurrence of bodies bearing 

 the same close relation to the unknown alco- 

 hol that marsh-gas bears to wood-spirit, or 

 acetic acid to common spirit of wine. As we 

 ascend in the series, however, wo meet with 

 the true alcohols, in which silicon takes the 

 place of carbon as the grouping element. 



In 1867 Buff and WOhler, on heating crystal- 

 line silicon nearly to redness in a current of 

 dry hydrochloric-acid gas, obtained a volatile 

 fuming liquid, afterward found to be the strict 

 chemical analogue of chloroform, silicon re- 

 placing carbon. When this is made to unite 

 with anhydrous alcohol, a colorless ethereal 

 liquid is obtained on distillation, having^ an 

 agreeable odor and a boiling-point of 184 C. 

 This body is strictly analogous in composition 

 to a substance obtained by acting on ordinary 

 chloroform with sodium alcohol. 



Ordinary chloroform is closely allied to 

 wood-spirit, or methyl nlcohol. In fact, 

 chloroform is easily obtained by treating wood- 

 spirit with bleaching-powder. Arguing from 

 analogy, we should look for a simple silicon 

 alcohol similar to wood-spirit, or methyl alco- 

 hol. As a matter of fact, no such alcohol has 

 as yet been produced even indirectly, but an 

 acid corresponding to formic acid (which is 

 one of the most remarkable products of the 

 oxidation of methyl nlcohol) is very readily 

 produced, and, what is more, this acid yields 

 an anhydride which is wanting in the corre- 

 sponding carbon series. Dr. Reynolds gives as 

 follows the formula) of two heptyl alcohols, the 

 one a silicon, the other a carbon alcohol : 



f C,H. 



8:1!: 



i OH 



This silico-heptyl alcohol is obtained by treat- 

 ing the product of the action of silicon upon 

 absolute alcohol with zinc, ethyl, and sodium, 

 decomposing the products with water in sealed 

 tubes, and then distilling. This alcohol i-* a 

 colorless liquid, not unlike wine alcohol. Chem- 

 ically it acts just like any of the other alco- 

 hols, producing ethers, and dissolving the 

 alkali metals to form sodium or potassium 

 alcoholates. At le-t one other compound of 

 this same order is known. On treating silicon 

 ethide a body prepared by the action of 

 chloride of silicon on zinc ethide in the same 

 manner we should adopt in preparing wood- 

 spirit from miirsh-gas, a colorless liquid, 

 lighter than and insoluble in water, is ob- 

 tained. It yields an ether with acetic acid, 

 dissolves sodium, forming an alcoholate, and 

 in fact conforms to the general habits of the 

 alcohols of the series to which the common 

 spirit belong!i. 



Thoti-h no well-defined alcohols have yet 

 been discovered in which silicon acts in any 



