hinders the action of diastase on starch. The lime-water should be made from caustic lime, and not be a mixture of chalk-and-water, which is not unfrequently the case. The operation of kneading, as usually performed, has many disadvantages; it is laborious, and it certainly is uncleanly. Many kneading-machines have been invented, but the hand-machine of Mr. Stevens is the one generally used. It is in use at the Holborn Union, where about 5632 lbs. of bread are turned out every week by one man and two boys; and they contrive to make ninety-six 4-lb. loaves out of every sack of flour (280 lbs.); the materials used on the average of a whole year being as follows: Many writers have recommended the use of unfermented bread, but few care to eat it, and it certainly is not so easily digested as bread made in the ordinary way. The best sample of unfermented bread is that known as aërated, made by Dr Dauglish's process. His method has this advantage, that during the whole of the operation neither the flour nor the dough comes in contact with the flesh of the workmen. This bread is found to agree better with some persons than bread made with yeast. The great objection brought against it is that it has a tendency to become disagreeably dry. It is easily digested and assimilated, and may even be eaten quite new by the dyspeptic without his feeling any of the discomfort which new leavened bread generally produces. It is certainly better for infants than ordinary bread. When taken from the oven the bread begins to lose weight. The 4-lb. loaf loses 11 ounce. The French munition loaf weighs 15 kilogrammes (33 lbs. avoirdupois), and contains two rations of 760 grammes (each 165 lb.) The ration of biscuit is 550 grammes (1.2 lb.) (Code des Officiers de Santé, 1863.) Nutritive Value of Bread.-The nitrogenous substance contained in bread is to the carboniferous as 1 to 6'3. It therefore requires more nitrogen for a perfect food. It is more digestible than flour. No satiety attends its use, although it may be always prepared in the same way. This is probably owing to the great variety of its components. A certain proportion of bread should form an addition to every meal. It should not be taken new. Fatal accidents have occurred from the distension of the stomach by an excessive meal of newly-baked bread. Young infants should not be fed upon bread-in various forms & practice common enough, but reprehensible in the last degree. Bread given to infants always occasions disorder, griping, and flatulence. The following tables illustrate the nutritive values of the ordinary English bread, and the bread of the French and Aus M. Poggiale analysed samples of bread supplied to ten different European armics, the But this, of course, is merely an average, and results we append:is subject to many variations. The weight of the loaves is generally taken when they are hot. The Austrian army authorities permit a loss of 2.9 per cent. in four days. In the French army different kinds of bread are used-ordinary bread, biscuited bread, bread half-biscuited, bread one-quarter biscuited, and hospital. The "pain biscuité" is used only on service. It is firmer than ordinary bread. Belgium Holland Stuttgart Austria Paris Grand Duchy of Baden Piedmont Winter. Spain Summer. Pain de munition ordinaire keeps 5 days. au quart biscuité demi | dition of new bread. These effects were produced alternately, many times in succession, upon the same piece of bread. A heat of about 131° (55° C.) was found to be sufficient to reconvert stale into new bread. The amount of bread daily consumed in Paris by each inhabitant has been calculated not to exceed 508 grammes (the gramme tity taken by each Londoner to be 350 grammes. New and Stale Bread.-Bread, as we have previously remarked, is more digestible the day after it is baked, for new bread is gummy in its nature, and is difficult of mastication. It is very generally supposed that the change which takes place in the properties of bread which has been kept for a few days is owing to the loss of water by keeping. This, how ever, is not the case. The crumb of newly-equals 15:432348 grains), and the mean quanbaked bread when cold contains about 45 per cent. of water, and that of stale bread contains almost exactly the same proportion. The difference in properties between the two depends simply upon difference in molecular arrangement. Boussingault found that a loaf which had been kept for six days, though it had become very stale, had not lost more than 1 per cent. of its weight when new. This same loaf was then placed in the oven for an hour, and at the end of that time it had acquired all the properties and appearance of new bread, although during the second baking it lost 3 per cent. of water. In another experiment, a portion of bread was enclosed in a tight case to prevent loss of water by evaporation, and allowed to become stale; it was then heated, and was thus restored to the con Fungi.-When bread has been kept a few days and has become stale, certain species of fungi are apt to become developed, such as Penicillium glaucum, which forms the green mould of cheese; the Fermentum cerevisiæ, or yeast fungus; the Oidium aurantiacum, an orange-red mould; the Puccinia graminis, and others. Diseases connected with the Quality of Flour and Bread.-The flour may be ergotised or grown, and fermenting with fungi forming. The continuous use of ergotised bread causes the poisonous symptoms of ergot, which in its most intense form gives rise to dry gangrene; in its less severe forms, to violent intestinal symptoms. Ergot is more common in rye-flour, but is also met with in wheat. Fermenting bread gives rise to indigestion, and acid bread to diarrhoea. Fungi, more especially the Oidium aurantiacum, also give rise to diarrhoea. - (BONDIN and FOSTER, Archives Gen. de Med., 1848, p. 244.) Oats attacked by the aspergillus (mouldi. ness) have given rise to paralytic symptoms in horses, so that these fungi should be looked upon with considerable suspicion. It is not known that the acarus, so common in flour, has any bad effects when eaten. See also articles ACARI and FLOur. In addition to the above, foreign observers have found borax, alabaster in powder, salep, and orris-root. Ammonia carbonate and magnesia carbonate are employed to realise the important consideration of producing light and porous bread from spoiled, or, as it is technically termed, sour flour. If carbonate of magnesia be used in large quantities, it may prove injurious to health; for during fermentation lactic acid is developed, and the carbonate of magnesia becomes converted into a lactate, which has a purgative action. Carbonate and bicarbonate of potash.-Both these salts are used for the same purposes as ammonia and magnesia. Marine salt has the effect of making the bread more compact, and hence heavier. In 1848 it was discovered that the bakers of Nantes had been in the habit of using salt which had been previously employed for the purpose of salting sardines, cod, &c. Heads of sardines and scales of the cod were even found in the bread. Borax has been discovered by M. Duville in second-quality bread; this adulteration was probably accidental. Chalk, clay, alabaster, and similar substances have been used with the object of increasing the weight. Barley, beans, peas, and dari are frequently mixed with flour. According to the evidence before the Adulteration Committee, wheat-flour is frequently mixed with as much as 25 per cent. of barley. Bean-flour is added not so much for the sake of profit, as with the object of rendering certain descriptions of flour more tenacious when made into dough, and is especially used as an addition to damaged flour; the proportions are from 1 in 40 to 1 in 60, or even more. Dari is an Egyptian grain, at one time imported for the purpose of mixing with wheaten flour. White peas improve the appearance of flour, but not the quality, and are put in to cheapen it. Water in excess.-The natural quantity of water has been estimated at 66 parts in 150; many practices are, however, resorted to to increase this amount. One of the principal means employed to attain this end is the addition of rice-flour, which, swelling up, absorbs more water than wheat-flour. Potatoes added in large quantities have probably the same effect. The addition of rice is highly reprehensible, as the amount of gluten contained in it is, when compared with wheat, excessively small, and potatoes are equally deficient in gluten. Another method employed to increase the quantity of water in bread is, after having incorporated with the dough as much water as possible, to put the loaf in a very hot oven; this causes the crust to form speedily, and thus the escape of water is prevented. The same object is to a certain extent effected by throwing sacks over the loaves when removed from the oven. Sulphate of copper.-Some few years since, the inhabitants of the Continent and this country were considerably startled by the discovery that many of the Belgian bakers were in the habit of mixing sulphate of copper with their bread, for the purpose of improving its appearance and making it lighter. This practice has also been resorted to in Holland and in some parts of France. In 1844 a whole Belgian family were poisoned from bread adulterated with sulphate of copper: before that date, in 1841 and 1843, several bakers were punished with great severity for this offence. The quantities used ordinarily to adulterate bread with this substance are, according to M. Kuhlmann, extremely small, viz., 47 grains to 200 loaves, each weighing 2-2 lbs. avoirdupois; there is, however, the danger of unequal admixture. sulphate of copper in 375 kilogrammes. The proportion which gives the greatest degree of lightness is from 350 to 138655 part to 1 part of dough. Should a larger quantity than this be used, the bread is too moist, it becomes very white, and acquires a disagreeable odour, similar to the smell of yeast. The largest quantity which can be employed without damaging the bread is 100 part to 1 part of dough. If the quantity used be larger than this, the bread is very watery, and presents large cavities; on the addition of part of sulphate of copper, the paste does not rise, fermentation is stopped, and the bread assumes a green colour. M. Malapert of Poitiers has discovered in the wafer-bread (pains à cacheter) of that town large quantities of vert métis (arsenite of copper). Each of these wafers, weighing about 20 grammes, contained about 30 to 35 per cent. of the poison. Tardieu informs us that specimens of the pains de gélatine have been found so highly coloured as, in point of fact, to consist only of a mixture of sulphate of copper and iron. In India, a vetch, Lathyrus sativus-Kessaree-dholl-is occasionally used with wheat and barley. Dr. Irvine in the "Indian Annals" has described a peculiar form of paralysis of the legs which this vetch, when it exceeds part of the flour, gives rise to. The L. Cicera has the same effect. Lime - water has been recommended by Liebig for the purpose of whitening bread made from musty or damaged flour. Microscopic Characters of Bread.-Under the microscope, starch-cells broken up into angular masses, or greatly enlarged, and stringy masses of gluten, are usually seen; besides this, high powers frequently discover bacteria in the shape of rods, the source of which is probably the yeast. Great care must be taken lest the serious mistake should be made of mistaking the many curious forms the brokenup wheat-starch presents for adulteration. By practice and the constant examination of the characters of unadulterated bread, and a practical knowledge of the appearance different starch-grains assume after being more or less changed in shape by cooking, it is possible to detect by the microscope rice-flour, bean-flour, and Indian millet; but barley-flour and potatoes both present great difficulties. There is very little difference in the shape of the barley starch-granule and that of the wheat, and in the process of bread-making the potatogranules are so changed as to confuse all their distinctive characters. Bone-dust and a few other mineral adulterations may also be detected by the microscope. Alum.-The custom of mixing alum with bread is a remarkably old one, at any rate in this country, and appears to have been practised from the earliest times. It is used to prevent an excess of fermentation when the altering gluten or cerealin acts too much on the starch, and it also whitens the bread; it does not increase the amount of water, as generally supposed, and it enables wholesome bread to be made from flour which otherwise could not be used. The dangers which are said to arise from this practice have probably been much exaggerated. The amount of alum added is really small; indeed, as Mr. Wanklyn has observed, the addition of large quantities of alum would render the bread unsaleable. Alum, Detection and Estimation of.-The detection of the presence of alum in bread is easily effected by Mr. Horsley's method. An alcoholic solution of logwood containing an excess of carbonate of ammonia colours alumed bread blue. To use the test, the bread-crumb is simply soaked in the liquid for six or seven minutes, and then squeezed. This will show the presence of alum in so small a quantity as 7 grains in the 4-lb. loaf. With such minute quantities the colour is of a light blue, and there are gradations of colour up to 30 grains, by which a practised observer can estimate the quantity of alum present. At about 30 grains the colour becomes so dark that the gradations are lost, and no approximation to the quantity of alum can be made by the eye. The obvious objection to the test is that carbonate of magnesia and some other substances also produce a blue coloration. Still the analyst, if the logwood test responds, knows that there is something wrong, and will submit the bread to a closer examination; while, if the test fails, it is certain the bread does not contain any appreciable amount of alum. Determination of Alum.-Of the numerous methods, good, bad, and indifferent, which have been proposed for the estimation of alum in bread, that worked out by Dupré (slightly modified by Wanklyn) is the one now generally practised. Its principle is this: the ash of bread consists of silica, common salt, phosphates of lime and magnesia, a trace of phosphate of iron, and, if alum be present, phosphate of alumina. Phosphates of lime and magnesia are soluble in acetic acid, phosphates of alumina and iron insoluble. The whole of the phosphates are therefore precipitated, the phosphates of alumina and iron separated by dissolving the others out, the alum and iron weighed, the amount of iron determined volumetrically, and the difference is the alum. The actual operation is performed by taking 100 or 200 grammes of bread, and burning it down to an ash, either in a muffle or a large platinum dish. The ash obtained is moistened with from 5 to 10 c.c. of strong hydrochloric acid, and then 30 or 40 c. c. of distilled water is added, the whole filtered, boiled, and the precipitate well washed with boiling water. The precipitate may be removed from the filter, burnt, and weighed. It consists entirely of silica. The phosphates are in the filtrate; the filtrate is accordingly treated with 5 or 10 c. c. of liquor ammonia, which precipitates the phosphates. Then the liquid is rendered powerfully acid by acetic acid, boiled and filtered. Phosphate of alumina, contaminated by a little phosphate of iron, remains in the filter. The amount of the latter substance is determined by a volumetric process (best by the ferrocyanide of potash test) calculated into phosphate of iron, and subtracted from the weight of the phosphate of alumina. Other Mineral Adulterations.-If any other mineral adulterant besides alum has been used, it cannot fail to be detected by a careful examination of the ash. The ash of bread varies from 13 to 2 per cent. Any weight beyond 4 per cent. most certainly must be looked upon with suspicion, and if no alum is found, may be examined for magnesia, &c. Bricks and Brick Fields - Brick-fields exhale a very peculiar unwholesome odour, the exact cause of which still remains obscure. The gases which are evolved from the kilns are carbonic anhydride, carbonic oxide, and sulphuretted hydrogen, mixed with sulphurous and muriatic acid fumes. Hence it is very quickly fatal if breathed in a concentrated form. In the burning of bricks household breeze is used as a fuel; in other words, refuse household ashes, and these nearly always contain salt. The alkali combining with the clay, and forming a fusible glass, sets the muriatic acid free, which escapes in the form of gas. The remedy for this is easy. The brickmaker need not use household breeze at all, but coke instead; or if he use household breeze, he can purify it from the salt by exposing it to the action of the weather for some time. It is mainly the acid fumes, which are certainly preventable, that destroy the vegetation around brick-fields to such a large extent. So loud have been the complaints in some parts of France of the effects of brick-making on the surrounding herbage, that in the north of France it is enacted-(1.) That bricks shall not be burnt within 50 mètres (544 yards) of the public road. (2.) That the ovens shall be covered with cloth and straw matting to protect the neighbourhood from the disagreeable effects of the smoke. (3.) Brick-fields are not allowed to be established neat nurseries; and (4.) the ovens are only permitted to be lighted at night. Persons whose property has been injured by the fumes arising from the brick-furnaces, can in France recover an indemnity from the owners of the brick-fields for the loss sustained. In England, in almost all the actions brought against brick-manufacturers, nothing more than a nuisance has been established. Workers at this particular industry are subject to many complaints. Those obtaining the clay, which necessitates their remaining for hours at a time on damp and humid earth, are frequently attacked with obstinate and weakening fevers. Those whose duty it is to knead the clay suffer from the same effects, and are subject to diseases which are likely to attack those whose lives are passed on damp soils. The workers who attend more particularly to the baking, suffer not unfrequently from disease of the eye. The grinders are subject to inflammation of the synovial sheaths and articulations of the hands. This particular state is termed by French writers craquement des ligaments.— (RAMAZZINI, TURNER, THACKRAH, HALFORD.) Public attention, in the year 1873, was particularly directed to the state of the children employed in our brick-fields by Mr. George Smith, who eloquently pointed out the degradation of their mental and physical nature, directly induced by the conditions under which they obtained a laborious livelihood. Mr. Smith at length succeeded in getting the Legislature to extend the principle of the Factory Act to the brick-fields. For the purposes of hygiène, hollow and waterproof bricks are the best-the first for ventilation and lightness, the last for preserving the dryness and integrity of our homes under all the vicissitudes of climate, season, |