Part 35 (1/2)
_Xantheine, or the Coloring Matter soluble in water._--By the preparation of the substance which colors yellow certain dahlias, it is at once perceived that it has no a.n.a.logy to xanthine. The latter is as known insoluble in water, while the coloring matter under consideration is readily soluble in water.
To obtain the xanthine we treat the petals of yellow flowering dahlias with alcohol, which quickly dissolves the yellow coloring matter, besides the fat and resin. The solution is evaporated to dryness, and the residue treated with water, whereby the fat and resin are separated.
The water is again evaporated to dryness, and the residue treated with absolute alcohol. The resulting solution diluted with water is mixed with neutral acetate of lead, which precipitates the coloring matters.
The lead precipitate is then decomposed with sulphuric acid, upon which the xantheine which remains dissolved in the water is purified by alcohol.
Xantheine is soluble in water, alcohol, and ether, but crystallizes from none of these solutions. Alkalies color it intensely brown. Its power of coloration is considerable. It dyes various fabrics of a yellow tone, which is without brilliancy. Acids again destroy the brown coloration produced by alkalies. Xantheine combines with most metallic bases, and forms therewith yellow or brown insoluble lakes.
The facts here related agree with all which has been previously observed regarding the coloring matters of flowers. It is known that blue flowers can become red, and even white, where their coloring matter is destroyed, but never yellow--and _vice versa_. These three coloring matters can generate the colors either alone or by admixture, which are seen in flowers; but whether they are the only matters which color flowers, we are at present unable to determine.--_Journal de Pharmacie._
IMPROVED PROCESS FOR BLEACHING BEES'-WAX AND THE FATTY ACIDS.
BY MR. G.F. WILSON.
This improved process consists of two parts:--1st, the application of highly-heated steam to heat the fatty matters under treatment, by which means the requisite heat for melting these substances is obtained, and at the same time the atmosphere is thereby excluded; the heated steam so applied in its pa.s.sage off, carries with it the offensive smells given off by the fatty matters, and being made to traverse a pipe or pa.s.sage up or along which gaseous chlorine is allowed to flow, a complete disinfection of the offensive products is thereby effected. 2dly, the treating of bees'-wax in a mixture of hard acid fat and bees'-wax, with compounds of chlorine and oxygen, preferring to employ that disengaged from chlorate of potash by treating it with sulphuric acid. For this purpose, Mr. Wilson takes at the rate, say, of a ton of yellow bees'-wax, and melts and boils it up with free steam for about half an hour. It is then allowed to stand a short time, and is then decanted into another vessel provided with a steam-pipe to emit free steam; about 20 lbs. of chlorate of potash is added, and the steam turned on; 80 lbs.
of sulphuric acid, diluted with a like weight of water, is then gradually added. The matters are allowed to stand for a short time, and are then decanted into another vessel, and again boiled up with free steam, and treated with a like quant.i.ty of diluted sulphuric acid. The bees'-wax is then decanted into a receiver, and is ready for use. The bees'-wax may, before undergoing these processes, be combined and boiled up with a hard fatty acid, and then treated as above described.
CHEMICAL EXAMINATION OF NAPLES SOAP.
A. Faiszt has submitted this celebrated shaving soap to a.n.a.lysis. He states that it is made by saponifying mutton fat with lime, and then separating the fatty acids from the soap thus formed, by means of a mineral acid. These fatty acids are afterwards combined with ordinary caustic potash to produce the Naples soap. He found that 100 parts of this soap contained
Parts.
Fatty acids, 57.14 Potash combined with the fatty acids, 10.39 Sulphate of potash, chloride of pota.s.sium, with a trace of carbonate of potash, 4.22 Silica, &c., 0.46 Water, 27.68 ----- 99.89 _Gewerbeblatt aus Wurttemberg._
MANUFACTURE OF SOAP.
The removal of the duty from soap, and the consequent emanc.i.p.ation of this branch of industry from the tender mercies of the Excise, has given a fresh impetus to the manufacture of this important article of daily use, and enabled some processes to be practically carried out in England, which, previous to the removal of the duty, could not be adopted in this part of her Majesty's dominions.
It will doubtless appear strange to those unacquainted with the circ.u.mstances, that owing to the mode of levying the duty by admeasurement, and not by actual weight, the maker of a particular kind of soap was debarred the privilege of manufacturing in this country.
Fortunately for him, the manufacture of soap being free from all Excise restrictions in Ireland, he was enabled to carry out his process in the sister kingdom, whence it was exported to England, and admitted here on payment of the Customs' duty, which was the same as the Excise duty on its manufacture here. All this roundabout method of doing business is now done away with, and no restriction now exists to mar the peace of the soap manufacturer.
Amongst various new processes lately introduced is that of Mr. H.C.
Jennings, which is practically carried out in the following manner:--
Combine 1000 lbs. of stearic or margaric acid, as free from elaine or oleine as possible, or palmatine, or any vegetable or animal stearine or margarine, at the temperature of 212 Fahr., with a solution of bicarbonate of potash or soda, specific gravity 1500. Constantly stir or mix until an intimate combination is obtained, and that the elements will not part when tried upon gla.s.s or any other similar substance. When the ma.s.s is cooled down to about 60 Fahr. add one pound per cent. of liquor ammoniae, specific gravity 880, and one pound per cent. of strongest solution of caustic potash; these are to be added gradually, and fully mixed or stirred until perfectly combined. Dissolve 15 to 18 pounds per cent. of common resin of commerce, by boiling it with a solution of subcarbonate of potash and common soda of commerce, in equal parts, as much as will give the solution a specific gravity of about 1800, when boiling hot. Mix these perfectly with the above-mentioned stearic or margaric acids, and carbonated alkali; then add a strong solution of caustic potash or soda, until a perfect saponification is produced. The dose of caustic alkali will much depend upon the purity of the stearine or margarine employed. The separation is now effected by using common salt, or sulphate of soda, &c., as is known and practised by soap manufacturers. If the soap intended to be produced is to be colorless, no resin must be employed, and a larger dose of liquor ammoniae and caustic alkali must be used, according to the dryness of the stearine matters to be operated upon.
A SIMPLE AND CERTAIN METHOD TO DETERMINE THE COMMERCIAL VALUE OF SOAP.
BY DR. ALEXANDER MuLLER.
In consequence of the ceremonious process by which the fatty acids are determined in one portion of the soap, and the alkali by the incineration of another, I consider the following method is not unworthy of publication, because it appears to afford quicker and more correct results by reason of the greater simplicity of the manipulation. It is available princ.i.p.ally for soda soaps, which are the most common; but it may be also employed with corresponding alterations for soaps which have other bases.
A piece of soap weighing two or three grammes is dissolved in a tared beaker gla.s.s of about 160 cubic centimetres capacity with 80 to 100 cubic centimetres of water, by heat, in a water-bath, and then three or four times the quant.i.ty of diluted sulphuric acid or as much as is necessary to decompose the soap, added from a burette. When, after repeated agitation, the fatty acids have separated in a transparent clear stratum from the aqueous solution, it is allowed to cool, and then the contents of the beaker gla.s.s are placed in a moistened filter, which has been previously dried at 212 Fahr. and weighed. The contents of the filter are washed until their acid reaction disappears. In the meanwhile the beaker gla.s.s is placed in a steam-bath, so that, it being already dry, may support the washed and partly dry filter, which is laid on the mouth of the gla.s.s as if it were in the funnel. The fatty acids soon pa.s.s through the paper, and for the most part flow ultimately to the bottom of the beaker gla.s.s; the increase of weight of which, after cooling, and the subtraction of the weight of the filter, gives the quant.i.ty of fatty acids present in the soap. A second drying and weighing is not necessary, if on the cold sides of the interior of the gla.s.s no damp is to be observed, which is occasioned by a trace of water still present. If the quant.i.ty of oxide of iron added to marble the soap is considerable, it may be easily found by incinerating the filter and determining the weight of the residue.