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the form of an extract; and after working half a year to obtain this result, I am so far satisfied. The extract is made with soft water, without milk, in a water-bath, carefully maintaining the above temperatures; this is continued for three or four hours; and twice repeated again for half an hour or an hour, which is not at all superfluous as the results obtained from 5,600 grms. of malt, and 4,480 grms. meal, are as follows:
1. Liquid obtained, 42 lb. of 1:110 sp. gr., at 18° C. = 26%, or 10.92 lb. extract.
2. Liquid obtained, 20-5 lb. of 1.057 sp. gr., at 18° C. = 14%, or 2.87 lb. extract.
3. Liquid obtained, 19-5 lb., of 1.027 sp. gr., at 18° C. = 61%, or 1.32 lb. extract.
Boiling the obtained results is not necessary; and indeed it is very easy to cause them to burn in some places. The quantity to be added of the bicarbonate of potash should be increased from 10% to 15%, on account of the more complete extraction of the meal substance; even then there results only a very weak but unmistakably alkaline reaction. The straining is best performed through a moderately fine hair sieve. The attempt to clear the liquid by standing or percolation is without results ; for after sixteen hours' standing in high cylinders, only to is clear, and % thick. It is therefore best, owing to the ill-keeping of the diluted liquid, to evaporate the extract with continual stirring, until it attains the proper consistence. The evaporation takes place over a water. bath in a kettle or saucer of closely calculated weight, after the sp. gr. of the liquid to be evaporated has been exactly estimated, in order to ascertain the amount of extract to be obtained from it. This latter may be done by means of the Balling's table for the estimation of malt extract from the sp. gr. of the beer wort, even if the thick extract liquid, by means of the starch globules contained therein, separates bodily from the clear beer wort. In the hot weather, it is advisable to continue the evaporation until the weight of the remainder in the estimated (or weighed) kettle contains 1} of the extract contents, calculated from the above table. In the first case is obtained a very tough, stringy extract; in the second a soft, but not flowing palp. The colour which, of course, does not depend on the malt, is ordinarily light brown; the taste, mild, rather sweet, and slightly mealy; the smell is that of malt; the watery solution dull, of a light grey colour, and of a very small colouring power. The solution, in a quantity of water, sp. gr. of 1:18–1.24, is thickflowing, and forms no visible sediment; the solution in 4-6 parts of water, is thin-flowing, and clears itself pretty quickly, although it does not become completely transparent, and after a short time, there occurs a distinctly visible precipitate, which, under the microscope, exhibits several undisturbed starch globules. The extract which has been evaporated to a stringy condition, keeps for months even in vessels that have been opened, and in the hot weather; the thinner extract inclines to turn mouldy; but this may be checked successfully by grating sugar over the surface. For the more easy dividing of it out into doses, it is advisable to dissolve the necessary quantity of extract required for one or two days in a proper quantity of water; if kept much longer, the solution turns sour, even when kept in a cellar.
If it is dissolved in milk, in proper proportions, a food is obtained which exactly resembles the freshly prepared food in smell, taste, and appearance; and it is readily taken by children who have been used to the freshly-made food. I cannot say the same of the socalled Liebe-Liebig's food. This latter has, at a sp. gr. of 1.391:40, the consistency of a very thick stringy substance; it is much more transparent, but on the other hand, much browner in colour, and forms only a small precipitate (sediment), in which, with the aid of a microscope, no starch globules are visible. On the addition of iodine solution, however, numberless particles assume a blue colour; and may be recognised as chemically unchanged starch globules, though they are broken and damaged.
The recipe of the extract is as follows :—110 to 115 (instead of 100) grms. bicarbonate potash, 3200 grms. of wheat meal of 2nd quality, 4000 grms. of coarse barley malt, are put, after 1 to 2 hours maceration, with 15 to 16 litres of soft water, in a water-bath, and during continued stirring at last brought to 64° to 66° C., and kept at this temperature for 3 to 4 hours; then the mixture is shaken, in not too large quantities, over a moderately fine hair sieve, washed round with small quantities of water, the residue again digeste with 7 to 8 litres of soft water for an hour to 64° to 66° C. The liquid portion separated by means of a hair sieve, and the remains again heated for half an hour with 5 to 6 litres of water, and strained as above. Out of the absolute weight and sp. gr. of the extracts the extract contained in them is calculated, according to the table of Balling, and evaporated in a full water-bath by incessant stirring in a calculated kettle up to 11, or at most 11, of the weight of the extract contents calculated.
The yield of dry extract, calculated according to the table of Balling, contains on an average 61 to 6 kg., or combined with 25 or 50 per cent. of water respectively, 8}, 83, 91, 10 kg. The thinner extract gives, on being dissolved in its own weight of water, a thick, chocolate-like liquid of 1:18 to 1:19 sp. gr. The same liquid is obtained by dissolving 5 parts of the thicker extract in 7 parts of water.
Of this solution one must dissolve for each dose 1 volume with 2 vol. water and 4 vol. milk, warmed to the heat of the blood, 34° to 36° C., never more, and then given to the children. The most scrupulous cleanliness of the feeding-bottles, corks, and especially of the indiarubber teats, is to be observed.
On the whole, the above mixture of ingredients yields 100 to 110 litres, or 1 kg. of the dissolved extract 6 to 7 litres of the food; while one bottle of the so-called Liebig's food, containing on an average 265 grms. extract, yields 3 litres of food according to Liebig's recipe.
Iodised Cotton. M. C. Méhu. (Journ. de Pharm., 4th series, xü., 388.) The author has employed cotton wool impregnated with 5 per cent. of iodine as a local application to glandular swellings of the neck in scrofulous patients with considerable success. He considers that it has considerable advantages over alcoholic or ethereal solutions of iodine, because these latter are powerful irritants to the skin, and often produce results which necessitate a suspension of the treatment for a time. The wool tinges the skin yellow without irritating it, and produces a marked sensation of warmth. It loses its iodine little by little, becoming decolorised, and should be renewed every two or three days. Placed on the neighbourhood of sores, it acts as a disinfectant.
The iodised cotton is prepared as follows:
Some iodine is reduced to very fine powder ; this is most easily effected by adding a few drops of ether from time to time, during the trituration. Some finely carded cotton wool of good quality and very dry is selected. The weight of the cotton taken should be at least ten times that of the iodine employed, but the author recommends 5 per cent. of iodine as the best strength.
Into a glass flask of about one litre capacity having a large mouth, furnished with.a glass stopper, is introduced the cotton in little pieces at a time, to each of which is added about its proper proportion of iodine, so as to divide the latter through the mass of the cotton. The flask is at first loosely stopped, and placed on a sandbath or in a heated stove. It is turned round in such a manner as to render the application of the heat uniform throughout. When the expanded air has escaped, the flask is entirely closed, and the heat continued until the iodine is vaporised, and the cotton has assumed the colour of roasted coffee. When this result is attained the iodine is fixed in the fibre and the operation is finished. When well conducted the process occupies about two hours. Twenty grammes of dry cotton to the litre flask is the most convenient quantity. The cotton may in this way be impregnated with 10 per cent. of iodine, but the half of this is generally sufficient. Even when charged with 10 per cent., the cotton retains in great part its tenacity; its colour is brown and not black, the latter result only occurring when the heat has been too great or too prolonged. Exposed to the air, the cotton gradually loses its iodine and becomes decolorised; it should therefore be preserved in stoppered bottles.
The author has tried preparing it by saturating the cotton with a solution of iodine in ether or sulphide of carbon, but the result was very inferior to that obtained by the foregoing process.
Iodised Albumen and Iodised Albumen with Iron Citrate. (Pharm. Centralholle, xiii., 1872, 97.) Professor Luigi Guerri, of Florence, at the instigation of Ghinozzi, has studied the question, whether it is possible to use white of egg as a means of preventing the decomposition of iron iodide, and to obtain a combination in which there is 1 part of iodine to 5 parts of oxide of iron. In order to study the influence of iodine upon white of egg, Guerri saturated white of egg with diluted phosphoric acid, filtered, and brought the solution of white of egg, to 3° B., adding to it finely divided iodine, which was procured by precipitating with water from tincture of iodine. The white of egg became red, but on being stirred it resumed its original colour. The same thing was repeated with several portions, antil at last the red colour remained, and starch paste became blue in colour. As soon as this point had been reached no more iodine was added, and the liquid after standing for ten or twelve hours, resumed its original colour, and gave no longer any reaction with starch flour, as was the case previously, which occurred, however, under the influence of chlorine water or nitric acid containing nitrous acid. One part of the iodine, however, could not be detected without first calcining with potash, in order to obtain it in the form of iodide of potassium.
Guerri has also found that even by evaporating white of egg to dryness the iodine remains bound, and during the iodisation white flakes are formed, which settle on standing, and can be again dissolved with the smallest possible quantity of caustic kali.
According to minute calculations by Guerri, 100 parts of iodised
albumen dried at 60° C., contain 3.132 of iodine, and give 474 parts of solution of white of egg of 3o Ar. B. 31.928 of iodised albumen dried at 60°, containing 1 part of iodine. Iodised albumen produces transparent yellow scales, which dissolve in water, with the exception of a few flakes which can neither be dissolved by acetic acid nor phosphoric acid, but only by alkalies. The solution is precipitated with alcohol ; it is neutral, and gives by itself no iodine reaction.
In order to obtain a preparation of iron of the before-mentioned strength, Guerri dissolves 18 parts of citrate of iron, corresponding to 5 parts of oxide of iron in 474 parts of solution of white of egg saturated with iodine as before described, of 3o Beaumé, and evaporates to dryness at 60°, out of which are obtained 50 parts of residue containing about of citrate of iron and of iodised albumen. The so-obtained preparation has the appearance of citrate of iron, only rather more yellow; the solution behaves in the same way as that of iodised albumen.
Both preparations can be made in the form of pills by means of syrup, or extracts free from tannic acid, or they can be given in the form of powder. Watery solutions can also be obtained from the evaporated as well as from the original liquid.
Iodised Milk. From Hoffman's most admirable report on the “Progress of Pharmacy," we make the subjoined extract, which has a practical value for the physician :-It is well known that milk takes up iodine, disguising its taste, smell, and colour, completely. Since iodine is an antiseptic, iodized milk keeps for some time. Dr. Hager calls attention to this fact, and suggests that this, perhaps, is the mildest form of administering iodine. Its therapeutic effect seems to be equal only to about one-fifth of the iodine. Hager thinks iodized milk will soon become a favourite form of administering iodine, and suggests the following mode of preparation : One part of iodine dissolved in ten parts of alcohol, admixed with ninety parts of fresh, warm cow's milk.