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ing in the fatty matters in the state of a margarate, stearate, or oleate, and therefore in the formation of a margarate, stearate, or oleate of potash or soda, soluble in water. It is easy to understand that a great variety of soaps must be manufactured to suit the various purposes to which soaps are applied in domestic and manufacturing concerns; and so we find that different qualities of soap are manufactured for boiling silks, clearing wool, or for clearing madder goods, and giving to the different colors obtained from this root a greater brilliancy and fixity. Strange to say, we are quite ignorant of the real composition which each of these soaps should present to produce the maximum of effect, and we are even unacquainted with the composition of those now employed. I have therefore thought that it might be interesting if I were to offer a statement of the results I have obtained in connexion with this point. To arrive at a medium, showing the real difference which exists between soaps employed for the above purposes, I have been obliged to make a great number of analyses. This will be easily understood if we reflect that the quality of the soaps used by different parties, in a given trade, is so little examined, that even the soap used by a single firm varies as much as 25 per cent. in quality. The following general results I have however arrived at in calculating the composition of these soaps as containing 30 per cent. of water:
Composition of Soaps per 1000 parts.
Water, From these results we find that the soaps employed vary in the quantity of alkali according to the nature of their application; thus in 1000 parts of soap, there are 21 parts more alkali in the one used for boiling silk, and 26 parts more alkali in that employed for clearing wools, than there are in the soap best suited for clearing madder purples. These facts show us at once how important it is to inquire into the real composition of a soap before employing it for a given purpose. If, on the one hand, a calico printer were to use a soap which had the composition of the one used by the wool scourer, he would cause the shade of his madder purples to fade; and if, on the other hand, the wool scourer were to employ the neutral soap of the calico printer, he would have but imperfect results, owing to this circumstance, that in the latter case an excess of alkali is essential, not that the alkali may combine with the fatty matters of the wool, but that it may form an emulsion with the stearine and elaine discovered by M. Chevreul, and thus liberate the dirt which they fix on the wool. There is another point which deserves the serious attention of calico printers, and that is, the influence which soaps of different compositions must have on the different shades obtained in madder dyeing; for it must be obvious that the soap containing a slight excess of alkali, which is the best suited for clearing madder reds or dark pinks, would deteriorate the beauty of the madder purples. In the first case, the dyer has in view, not only to fix and brighten his reds or pinks, but further to remove the yellow coloring matter, and also partially the red; whilst in the latter a soap
II. 29.3 64.0 6.3 0.4
26.00 66.00 7.56 0.43
V. 45.00 46.01 5.80 2-19
38.0 55.4 6.1 0.5
containing as little alkali as possible appears to me to give the best results. I have found by experiment the two following soaps to be best suited for these purposes:-
Soap for purples.
dark pinks. Fatty matter,
Water, Still we find that calico printers in general employ the same quality of soap for all shades of madder goods. Some dyers think that they overcome this difficulty by employing less or more of the same soap; but this is an error, not only as manifested by the above remarks, but because, as we shall show presently, the different soaps sold in the market, offer in their relative compositon differences which are equal to the different proportions they are in the habit of using for given styles or shades of madder prints. This fact can be easily proved by examining the qualities of soap which are supplied to a firm during a period of twelve inonths; for we find, as the following results show, that ihe quality of soap sometimes varies as much as 25 per cent. in value:
Impurities, The figures also show that the quantity of the real effective agent, viz: the fatty matter, in a soap may vary from 46 to 66 per cent.; consequently it may
be seen that a large sum of money is wasted by some of our large firms annually, for want of paying proper attention to one single article. It must be remembered that each piece of madder-dyed goods requires from 1 oz. to 4 oz. of soap to clear it. If we take the average at 2 oz. per piece, and admit that a print-works produces 100,000 pieces per annum, the quantity of soap used would be 12,500 lbs.; and if the soap be 25 per cent. under value, the loss would equal 4125 lbs.
It may be objected that the above soap was supplied to one firm only, and therefore its variation in quality might be owing to the inattention of persons connected with the firm. This remark would however have no value, as I have found similar differences of quality in the soap of other firms.
There is another fact connected with the use of soap by calico printers which deserves most serious consideration, and to which attention has not, so far as I am aware, been drawn, viz: that soaps are not at the present day, as formerly, made with one kind of fatty matter, but are manufactured sometimes from palm-oil, at other times with vegetable Auid oils, such as rape-seed oil, galipoli oil, again with animal fatty matters, and Jastly with the oily liquid called oleine, which is obtained when solid fatty matters are submitted to pressure to obtain a fatty matter having a higher fusing point, and consequently more fit for the manufacture of composite candles. The liquid oleine, containing small amounts of margarine and stearine, is extensively employed at the present day in the manufacture of soaps. I have ascertained from direct experiment, that such a soap will not give the same brilliancy and fixity of color to the shades obtained from madder roots as a soap made with a vegetable oil composed of margarine and oleine; or with an animal fatty matter composed of margarine, stearine, and oleine; consequently if a dyer uses a soap of the former composition, it will prove, if not a direct loss to him, at least an injury to his goods, in disabling him from producing the maximum effect. I should also mention here, that I have found in print-works household soap of an inferior quality, and containing 10 per cent. and upwards of resins. These soaps have none of the properties required in calico printing, and must therefore prove a loss to the printer, as well as those soaps which are sometimes found to contain glue. I hope these facts will prove how highly desirable it is, that, with the existing competition both amongst our local firms and those of the continent, the indifference which exists as to the qualities of the drugs employed in printworks should cease, and that science united with practical knowledge should step in, and guide the application of chemical art in manufactures. Then, and then only, will our manufacturers progress in a sound and remunerative manner.
I have also examined a great variety of soaps employed for domestic purposes, and have found their qualities to vary materially, as the figures underneath show:
Some Remarks on the Probable Present Condition of the Planets Jupiter and Saturn, in reference to Temperature, Sc. By JAMES NASMYTH.
Read at the Meeting of the Royal Astronomical Suciety. (Communicated by the Author for the Journal of the Franklin Institute.) The remarkable appearances which characterize the aspect of the planets Jupiter and Saturn, as revealed by the aid of very powerful and excellent telescopes, bave induced some reflections on the subject of their probable present condition as to temperature. With a view to excite more special and careful observation of the phenomenon in question, and promote discussion on this interesting subject, I have been tempted to hazard the following remarks, which may perhaps prove acceptable to some of the members of the Royal Astronomical Society.
“In a former communication, in reference to the structure and condition of the lunar surface, I made some remarks on the principle, which, as it appears to me, gives the law to the comparative rate of cooling of the planets; namely, that while the heat-retaining quality was due to the inass of the planet, the heat-dispensing property was governed by its surface; and as the former increases as the cube of the diameter of the planet, while the latter increases only as the square of its diameter, we thus find that the length of time which would be required by such enormous planets as Jupiter and Saturn to cool down from their original molten and incandescent condition to such a temperature as would be fitted to permit their oceanic matter to permanently descend and rest upon their surface, would be vastly longer than in the case of such a comparatively small planet as the earth.
"Adopting the results which geological research has so clearly established as respects the original molten condition of the earth, as our guide to a knowledge of the condition of all the other planets, it appears to me that we may in this way be led to some very remarkable and interesting conclusions in reference to the probable present condition of such enormous planets as Jupiter and Saturn, tending to explain certain phenomena in respect to their aspect.
“Assuming as established the original molten condition of the earth, and going very far back into the remote and primitive periods of the earth's geological history, we may find glimpses of the cause of those tremendous deluges, of which geological phenomena afford such striking evidence,* and by whose peculiar dissolving and disintegrating action on the igneous formations which at that early period of the earth's history must have formed the only material of its crust, and may in that respect obtain some insight into the source whence the material which formed the first sedimentary strata was derived. If we only carry our minds back to that early period of the earth's geological history, when the temperature of its surface was so high as that no water in its liquid form could rest upon it, and follow its condition from such non-oceanic state to that period at which, by reason of the comparatively cooled-down condition of its surface, it began to be visited by partial and transient descents of the ocean, which had till then existed only in the form of a vast vapor envelope to the earth, we shall find in such considerations, not only the most
The deluges here alluded to are quite distinct from those which have so frequently during various periods of the Earth's Geological History, swept over vast portions of its surface, and of whose tremendous violence we have such clear evidence, in the denudation of the hardest rocks, the debris of which has yielded the material of nearly every sedimento ary formation, from the period of the old red sand stone formation upwards.
These vast and often repeated deluges I consider to have resulted from mighty incur. sions of the ocean over vast portions of the earth's surface, which till then were dry land. The retreat of the matter below the earth's surface resulting from the progressive contrac. tion, consequent on its gradual cooling, must have again and again permitted extensive portions of the sold crust of the earth to suddenly crush down, like an over-loaded ill supported floor, and so allowed the ocean to rush in with fearful violence, and to occupy the place of the so submerged continent.
Judging from the facts which Geological Phenomena yield us in abundance, these incursions of the ocean must have been sudden, violent, and of frequent occurrence.
The sudden sinking down of a continent to the extent of 1000 feet in depth, would be but an insignificant adjustment of the crust of the earth to the retreating or contracting interior, as compared to its actual diameter (being only about one forty-thousandth part), but yet such a subsidence occurring to any portion of a continent near the sea, would occasion a rush of waters over its surface, amply sufficient to perform all the feats of violence and denudation which have taken place during many successive periods of the earth's Geological History, and of the occurrence and action of which we have most palpable evidence, not only in the vast accumulations of debris, caused by these violent incursions of the ocean, but also in the prodigious dislocations of strata, which have resulted from the crushing down of the crust of the earth, in its attempts to follow down and fill up the void or hollow spaces caused by the contracting and retreating Nucleus, which, as before said, I con. sider to be the true cause of this class of deluges, the tremendous violence of which has yielded the old red sandstone, and all other sandstones, conglomerites, boulders, gravel, sand, and clay. Vol. XXV.-THIRD SERIES.—No. 6.-June, 1853.
sublime subject of reflection in reference to the primitive condition of our globe, but also, as it appears to me, a very legitimate basis on which to rest our speculations in regard to the probable present condition of Jupiter and Saturn,—both of which great planets, I strongly incline to consider for the reasons before stated, are yet in so hot condition, as not only not to permit of the permanent descent of their oceanic matter, but to cause such to exist suspended as a vast vapor envelope, subject to incessant disturbances by reason of the abortive attempts which such vapor envelope may make in temporary and partial descents upon the hissinghot surface of the planet.
“Recurring again to this early period of the earth's geological history, when it was surrounded with a vast envelope of vapor, consisting of all the water which now forms the ocean. The exterior portion of this vapor envelope must, by reason of the radiation of its heat into space, have been continually descending in the form of deluges of hot water upon the redhot surface of the earth. Such an action as this must have produced atmospheric commotions of the most fearful character; and towards the latter days of this state of things, when considerable portions of what was afterwards to form our ocean came down in torrents of water upon the then thin solid crust of the earth, the sudden contraction which such transient visits of the ocean must have produced on the crust of the earth would be followed by tremendous contortions of its surface, and belchings forth of the yet molten matter from beneath, such as yield legitimate material for the imagination, and the most sublime subject for reflection. The extraordinary contortions and confusion which characterize the more primitive sedimentary strata, such as the gneiss, schist, and mica slate, in so very remarkable a degree, shadow forth the state of things which must have existed during that period, when the ocean held a very disputed residence on the surface of the earth.
“Could the earth have been viewed at this era of its geological history from such a distance as the planet Mars, I doubt not it would have yielded an aspect in no respect very dissimilar to that which we now observe in the case of Jupiter: namely, that while the actual body of the earth would have been hid by the vast vapor envelope then surrounding it, the tremendous convulsions going on within this veil would have been indicated by streaks and disruptions on the surface, which would be mottled over with markings such as we observe in the case of the entire surface of Jupiter: and by reason of the belchings forth of the monstrous volcanoes which at that period must have been so tremendously active on the earth, the vapor envelope would be most probably marked here and there with just such dingy and black-and-white patches, as form such remarkable features about the equatorial region of Jupiter-probably the result of volcanic matter, such as ashes, &c.,—which the volcanoes about his equator may from time to time vomit forth, and send so far up into the cloudy atmosphere as to appear on the exterior, and so cause those remarkable features which so often manifest themselves on the outward surface of his vapor envelope; for I doubt if we have ever yet seen the body of Jupiter, which will probably remain veiled from mortal eyes for countless ages to come, or until he be so cooled down as to permit of a permanent descent on his surface, of his ocean, that is to be.
“In applying these views to Saturn, it occurs to me that we may ob