CHEMISTRY. 



117 



mllii-iriit quantity of the product is dissolved 

 r at 'in ('., ami the goods are worked 

 tlii-i in tlio n-ual IIIMIUUT. Th.-y are then 

 I through boiling birliromato of potash, 

 li.\f> the color. The following addi- 

 tional particulars are taken from a paniphl.-t 

 issued by the " Patent- Farbon-Fabrik " of Got- 

 tinge n an establishment devoted to the manu- 

 tacturo of the new colors: 



The Societe" Induatrielle of Muhlhausen has found 

 tluit those colors attach themselves permanently to 

 liiu fibre, by the mere evaporation of the water in 

 which they" uro dissolved a circumstance of great 

 importance in calico-printing. All the colors are 

 soluble in water, and are precipitable by mineral as 

 well aa organic aci.ls and metallic salts. The col- 

 ors huvo a remarkable affinity for both animal and 

 vegetable fibres, upon which they have no injurious 

 action. 



The new colors dye wool, silk, linen, and cotton, 

 equally well. Hence mixed goods can be dyed in 

 one operation without appearing checkered, the color 

 producing one and the same tone of equal intensity, 

 both upon the weft and the warp. In dyeing, after 

 the color and the chrome baths, tin- goods are passed 

 through a boiling soda-bath, and washed in abun- 

 dance of water. Animal fibre may require the ad- 

 dition of a little acetic acid to remove the last traces 

 of alkali. Other metallic salts may be used instead 

 of chrome, according to the particular effect desired. 



Cyanogen in Bromine. Dr. T. L. Phipson 

 states that he has found in what purported to 

 be pure bromine, prepared for medicinal use, a 

 notable amount of cyanogen. It has been known 

 for many yearp that, in the manufacture of 

 iodine, a certain quantity of that dangerous 

 compound, iodide of cyanogen, sometimes finds 

 its way into one of the glass condensers ; and 

 a similar compound with bromine may occur 

 in this liquid element a more serious case than 

 the other, since it is dissolved and riiasked in 

 the liquid. Its presence in br6mine, says Dr. 

 Phipson, may be detected in the following 

 manner : Take an equal weight of iron-filings 

 (say half an ounce) to that of the bromine, and 

 add to the iron-filings four or five times their 

 weight of water ; mix in the bromine very 

 gradually, and stir all the time, filter rapidly 

 while warm from the reaction, place the filtered 

 liquid in a partially-closed bottle, and in the 

 course of some hours a deposit of ferricyanide 

 of iron (Berlin blue) will have formed, and may 

 be collected on a filter. In the course of two 

 days (with the above quantity) the whole of 

 the cyanogen is thus eliminated. 



Soluble Starch. According to Musculus, the 

 best mode of preparing soluble starch is as fol- 

 lows : Put 400 grammes of starch in a flask 

 containing two litres of a solution of sulphuric 

 acid of T^J. Heat until the solution is effected. 

 Then add chalk to arrest the action of the acid, 

 filter, and evaporate to a syrupy consistence; 

 filter again to separate the calcic sulphate, and 

 set aside in a cool place. After twenty-four 

 hours have elapsed, the solution begins to cloud, 

 and finally gives a bulky, white deposit of solu- 

 ble starch, which may be separated and washed. 

 If left for some time in contact with water, it 

 slowly dissolves, a little sugar being produced. 



Its rotatory power ia nearly four time* that 

 of anhydrous glucose. Alcohol precipitate* it 

 from its -olntioii in an insoluble Htuto. 



\'</lue of Chloralum as a Disinfectant. In 

 tin- ((Jrrmani (Jn>irterly Journal of 1'r 

 Pharmacy, Prof. D. N. Fleck discuiwc^ 

 fully the value of the various chloralum prepa- 

 rations chloralum liquid, chloralum powder, 

 chloralum wool and wadding. A translation 

 of this paper appeared in the American Chem- 

 it for July. To determine the value of chlora- 

 lum as a disinfectant, equal volumes of liquid 

 sewage were treated with that and five other 

 disinfecting agents, and the clear supernatant 

 liquid tested with alkaline silver solution for 

 its percentage of putrefying matter. It waa 

 thus found that 



Chloride of lime disinfects 100.0 / putrefying matter. 



Caustic lime B4.6 



Alum 80.4 



Sulphate of Iron 76.7 



Chloralum 74.0 



Chloride of magnesium 57.1 



From the data set forth in this paper, the 

 author concludes that 



1. Chloralum preparations are chiefly mixtures of 

 chloride of aluminum. 



2. They contain chlorides of lead, copper, and ar- 

 senic, which render them dangerous, especially as 

 internal medicaments, or as astringents for fresh and 

 suppurating wounds. 



3. The price of chloralum preparations is exor- 

 bitant, considering their composition and efficacy. 

 Where, as in case of the liquid chloralum, a net profit 

 of at least 700 per cent., or, as in the case of the wad- 

 ding, a clear profit of at least 4,000 per cent., can be 

 easily calculated, the limits of sound and solid busi- 

 ness are transgressed. 



4. Chloralum and the preparations thereof belong 

 to that class of unworthy secret preparations which 

 the public should be warned decidedly against buy- 

 ing. 



Effect of Acid on Iron Wire. At a meeting 

 of the Massachusetts Philosophical Society, 

 some iron and steel wire was exhibited, on 

 which certain curious effects had been produced 

 by the action of sulphuric acid. The soft char- 

 coal wire had become short and brittle, and 

 its weight increased. More remarkable still, 

 when the wire was broken, and the face of the 

 fracture wetted, it frothed as though the moist- 

 ure acted as a powerful acid. Exposure to the 

 air for a few days, or to radiant heat of a fire 

 for a few hours, caused these effects to disap- 

 pear. Prof. Osborne Reynolds having under- 

 taken the investigation of these phenomena, 

 soon observed that, on breaking off a short 

 piece from the end of the wire, the two fresh 

 surfaces behaved very differently : that of the 

 long piece, on being wetted, frothed for some 

 seconds, while that of the short piece was 

 nearly inactive. This seemed to imply that the 

 gas was not generated on the fresh surface, 

 but that it came from a considerable depth 

 beneath it. Prof. Reynolds hence concluded 

 that the effect was due to hydrogen having 

 entered into combination with the iron during 

 it* immersion in the acid; when the iron waa 

 exposed, the hydrogen gradually passed off. 



