صور الصفحة
PDF

flour into the trough, and take a little less than one quarter of the sack of flour, and pin or block it up to one end of the trough with the pin board. Then bring the seasoning tub with the ferment in it to the trough, pour in a sufficient quantity of warm water, (in summer, cold,) stir up the mixture with the hands, and mash any lumps of potatoes that may be in it. Next, strain it through a sieve, to separate the skins of the potatoes; then pour the mixture liquor into the flour which had been previously pinned or blocked up at one end of the trough, and mix it well into the flour with the hands. Sprinkle a little flour over the top, and let it stand 5 or 6 hours, during which time the sponge will have risen twice. The first rising is suffered to break and go down. In about an hour or so, according to the heat of the bakehouse, the sponge rises a second time, and just as it is about to break again, or when the air escapes by the bursting of the bubbles, about 3 pailfuls of water to make up the bateh are poured into the sponge from the seasoning tub, the water having dissolved in it about 4 lbs. of salt and 8oz. of stuff, (some use 16 oz. of stuff, or even more.) The liquor ought to be well mixed with the sponge; wliich being done, the pinboard is taken away, and the whole of the flour is worked up into one mass, which is blocked up by the pin-board to one end, and left about an hour in summer, and 2 hours in winter to prove. The vacant part of the trough is then sprinkled with flour, to prevent the dough from sticking, the pin-board is knocked out, and the dough is pitehed out of the trough on the lid of the opposite trough, when it is cut into masses and weighed, or scaled off as it is

After setting the batch, that is, placing the loaves in the oven, (Kg. 230,) which requires a good deal of skill, a set-up is placed in front of it. The potatoes for the next ferment are put into a kettle, and placed

[graphic]
[graphic]

Fig. 22g. Scaling Off.

called. These masses are then moulded into shape, and put aside in a regular manner to be fmally moulded into loaves, taking care to mould those first which were first scaled off. Previous to moulding, the oven must be well swabbed out, and the up-sets chalked, to prevent the bread sticking to them. They are then placed at the back and on each side of the oven by means of the peel. The long loaves, or the quartern and half-quartern bricks, arc put into the oven, packed together as close as possible. The common round bread is also packed close, but the cottage bread must be placed separately, each loaf by itself, or it will not be crusted all round.

Fig. 230. The Ovkk.

in the oven to boil. When the potatoes are done, and while still hot, the ferment for the next bateh must be mixed. Twenty-four hours elapse from the mixing of the ferment to the time when the bread is taken out of the oven.

In this process we see that the London baker in the manufacture of bread makes use of potatoes, yeast, flour, water, salt, and stuff. A few remarks are necessary respecting each of these ingredients.

As a sack of flour weighs 280 lbs., the addition of so small a quantity of potatoes as 8 lbs. cannot be for the purpose of adulteration. It is true that some of the cheap-bread bakers use a very much larger proportion, with a frandulent intention, potatoes being cheaper and less nutritious than a similar weight of wheat flour. There is, however, nothing injurious to the health of the consumer in the practice, and the addition of 7 or 8 lbs. of fruit, as the bakers term it, to a sack of flour, is said to assist fermentation, and to improve the appearance of the bread.

A far more objectionable material is alum, which is used by the bakers under the name of stuff Ot rocky. Its object is to bleach the bread, but the manner in which it acts as a bleaching material is by no means understood. It is, however, positively stated that if it be omitted, the bread, instead of being white, is brown. The proportion of alum to a sack of flour is much less than is generally supposed; and it is even less than the bakers themselves are aware of, for as they are liable to a heavy fine if alum be found on the premises, they purchase packets of stuff ready prepared for them by the druggists. The bakers suppose this to be ground alum, whereas, it actually consists of 1 part alum and 3 parts of common salt. This mixture is sold in pound packets at 2d. each. 8 oz. of this stuff are used to a sack of flour, so that the quantity of alum is only 2 oz. to 280 lbs. of flour, a quantity too small to have any injurious effect on the health. The presence of alum also causes the loaves to break from each other with a much smoother surface than if it were absent. It is stated that gypsum, chalk, pipe-clay, and blue

and white vitriol have been used to adulterate bread. These are most pernicious adulterants. Ground bones are also mentioned among the adulterants, but the reduction of bones to a powder fine enough for the purpose of adulterating flour would be more costly than the flour itself. Wo believe, however, that the chief adulterant of bread is in the flour itself, good flour being adulterated with an inferior flour, or with the flour of beans or peas. These, together with potatoes, are perfectly harmless. The great objection to their use is tha| the customer pays for them the same price as he would do for the fme flour.

Salt is a necessary article of food, and it is added to bread for the purpose of flavour. If the quantity be large, the bread retains more moisture than it otherwise would, and thus weighs heavier. But the taste of such bread sufficiently indicates its bad quality; it is rough in the grain, and two adhering loaves generally separate unevenly. The usual allowance of salt is an ounce to the quartern loaf; but the salt may be introduced by combining its constituents in the dough, for which purpose the flour is mixed up with a solution of carbonate of soda, and then a solution of muriatic acid is added. The carbonic acid thus disengaged will supersede the use of yeast, and will form, when baked, a light and excellent bread.

The usual method of fermenting bread is by means of yeast. This is obtained from the London brewers, or is manufactured for the purpose, as already noticed. Ale-brewers' yeast is well adapted to the purpose, but it cannot be obtained in sufficient quantity. The yeast of the porter-brewer is too bitter and too highly coloured to be used without a previous washing. Distillers' yeast has neither bitterness nor colour, but it is scaree. In warm climates, where yeast cannot be had, other ferments are substituted. In the East Indies bread is raised by means of a liquor called toddy, which flows from the cocoa-nut tree when its branches are cut. It ferments so rapidly, that in two or three hours it becomes an intoxicating liquor. In the West Indies dander is used. This is a liquor remaining in the still after the distillation of rum.

The flour ought to be some weeks old before it is made into bread. A sack of flour weighing 2801bs., and containing 5 bushels, generally produces 80 loaves. According to this, £th of the loaf is water and salt, and $ths flour; but the number of the loaves depends on the goodness of the flour. Good flour requires more water than bad, and old flour more than new; 82, 83, or even 86 loaves may in some cases be made out of a sack, and in other cases scareely 80. There is a considerable loss of weight in baking, the average loss in a quartern loaf being 9J oz., or not quite |th. If we take the loaves as peck, half-peck and quartern, the following were found within 48 hours after baking to be the weights before and after putting in the oven:—

Before. After.

lbs. oz. dr. lbs. Ob. dr.

Peck .... 19 12 0 avoirdupoise. 17 6 0

Half-peck . 9 14 0 — 8 11 0

Quartern. . 4 15 0 — 4 5 8

The loaf which presents the greatest surface in the oven loses most weight.

In the time of bad harvests, when the wheat is damaged, the flour may be considerably improved, without any injurious result whatever, by the addition of from 20 to 40 grains of carbonate of magnesia to every pound of flour.

The water used in making bread ought to be of good quality. It is stated that if the flour be kneaded with water saturated with carbonic acid gas, no yeast is necessary, and that bakers who live near Selzer water springs may substitute such water for yeast.

The Bakers of London constitute the nineteenth Company. They were incorporated about the year 1307, and consist of a master, 4 wardens, 30 assistants, and liverymen, and commonalty.

An expeditious and simple method of makiug bread for a small family is thus described in the Guide to Trade :—Take half a bushel of flour, and put it all except about 4lbs. into a tub or pan, and in winter place it before the fire to warm. Mix 6 or 8 ounces of powdered salt with the flour, or work it in with the dough. Then take a pint of good fresh yeast, and mix it well with a sufficient quantity of water at a blood heat. Make a deep hole in the middle of the flour; pour the water and yeast gradually into it, mixing the whole together with your hands until they are well incorporated. Cover this mixture up, and place it ncar the fire fill it is well risen. Then work the remaining flour into it with, your fists till it become a nice, smooth, tough dough. Make this dough into loaves, and bake in an oven properly heated. It will take from 1J to 2 hours in baking, but the bread should always remain in the oven half an hour after it has become brown, or it will not be soaked through.

For larger bakings, put the flour into a trough or tub sufficiently large to allow^ the dough to swell. Make a deep hole in th? centre of the flour. For half a bushel of flour take a pint of thick fresh yeast (not frothy), and mix it with a pint of fresh warm water, not too hot. Then gently mix with the yeast and water as much flour as will make it into a stiff batter. Pour this mixture into the hole in the flour, and cover it by sprinkling it over with flour. Then place over it a flanncl or sack, and in cold weather place it near the fire, but not too near. When the sponge has risen enough to crack the dry flour with which it is covered, sprinkle over the top 6 oz. of salt (more or less according to taste). Then work it with the rest of the flour, and add from time to time warm water till the whole is sufficiently moistened, or scareely so moist as pie-crust. Next work it well by pushing your fists into it, then rolling it out with your hands, folding it up again, kneading it again with your fists, till it is completely mixed and formed into a stiff, tough, smooth dough. Form your dough into a lump like a large dumpling, cover it up and keep it warm. After rising for about 20 or 30 minutes, make it into loaves, having shaken a little flour over the board to prevent sticking. The loaves may be made up in tin moulds, or you may divide the dough into equal parts according to the size required, and make each part into the form of a dumpling, and lay one of these upon another, then put the loaves into the oven, and bake for l£ or 2 hours.

Tn the Pharmaceutical Journal several recipes arc given for making unfermented bread. In a paper by Mr. H. Deane, contained in the third volume, the following recipe, by Dr. Smith, of Leeds, is given:—

5 lbs. of flour.

■£ oz. (apothecaries' weight) of sesquicarbonate of soda.

5 drachm of sesquicarbonate of ammonia.

4 drachms or teaspoonfuls of common salt.

Mix these intimately together, and then add the following solution: 50 oz., or 2j pints, imperial, of cold water,

5 drachms of hydrochloric acid.

This bread is easily made, requires little labour, no kneading, or time for the dough to rise. It costs a trifle more than bread made with yeast, but has the advantage of keeping longer without turning mouldy or sour, and is wholly free from any bitter or unpleasant taste. Its dietetic properties arc of the utmost importance. Common bread is liable in weak stomachs to turn sour, and produce heartburn and flatulency, and to aggravate cases of dyspepsia; but bread made by the new process is free from these baneful effects. Its daily use in health prevents these symptoms, and in many cases it corrects that morbid condition of the stomach and intestines on which these symptoms depend. It is useful in assisting to restore the biliary, and especially the renal, secretions to a healthy condition, as well as in the treatment of various cutaneous eruptions, originating in disorder of the digestive functions.

Mr. Deane's recipe is as follows :—

4 lbs. flour.

£ oz. (avoirdupois weight) of bicarbonate of soda.

4j fluid drachms of hydrochloric acid (specific gravity 1.16).

£ oz. common salt.

40 fluid ounces, or 2 pints imperial, of cold water.

Mix the soda perfectly with the flour, and the acid with the water, then the whole intimately and speedily together, using a flat piece of wood, or spaddle, for the purpose. It may be made into 2 loaves, and put into a quick oven immediately. It will require about li hour to bake.

In this kind of bread, kneading will prove injurious, by making it too heavy. The dough must not be too stiff.

BREAKWATER. An artificial barrier, designed to break the force of the waves in sea-ports and

harbours, and thus to protect the shipping from serious damage. Breakwaters are of various kinds, according to the nature of the roadstead or harbour, and the number of ships resorting thereto. In some cases, the roll of the waves is sufficiently checked by sunken vessels placed across the entrance of the harbour; in others, by moles, or piers projecting from the land; but there are cases, such as that of Plymouth Sound, where a large assemblage of ships cannot find a safe place of rendezvous without an erection of far greater magnitnde than these. Plymouth Breakwater presents a very remarkable instance of human skill and perseverance, successfully applied. It consists of an immense number of blocks of stone, thrown into the Sound, until a barrier nearly a mile in length was raised above the surface of the water, stretehing across the Sound, and leaving entrances at both ends. This great undertaking was commenced in August 1812, and so early as the end of the second year, about eight hundred yards of the breakwater began to appear at low-water, and the swell was so much broken that ships of all sizes began to take shelter within the breakwater, and fishermen within it could not jndge of the weather outside the Sound. Some limestone quarries near the Catwater were purchased of the Duke of Bedford for 10,000/., and about fifteen vessels were constantly employed in conveying the masses of stone (varying in weight, from one ton to ten tons) to their destined place. Many ingenious devices were employed to hasten the progress of the work, so that, during the first five years, the amount of stone deposited gradually rose from 16,000 to 300,000 tons per annum. The large masses were first lowered, and then smaller stones, quarry rubbish, rubble, and lime screenings, to fill up the cavities and form a compact mass. This structure was completed in March 1811, with the use of 3,369,261 tons of stone, and at the cost to Government of nearly a million and a half of money. The construction of this breakwater was at the time an object of the greatest interest in our own country, and to foreigners visiting us. A celebrated French engineer (Dupin) described in terms of high praise the working of the quarries, the order, regularity, and activity visible in all the operations, the embarking and disembarking of the materials, &c. "Those enormous masses of stone," he says, "which the quarrymen strike with heavy strokes of their hammers; and those aerial roads of flying bridges, which serve for the removal of the superstratum of earth; those lines of cranes, all at work at the same moment; the trucks all in motion; the arrival, the loading, and the departure of the vessels; all this forms one of the most imposing sights that can strike a friend

Inside towardsPlymouth luTidinvf itairt.

[graphic]

lOOO yarviS .

to the great works of art. At fixed hours the sound of a bell is heard, in order to announce the blasting of the quarry. The operations instantly cease ou all sides; all becomes silence and solitnde. This universal silence renders still more imposing the noise of the explosion, the splitting of the rocks, their ponderous fall, and the prolonged sound of the echoes."

The vessels employed for transporting the stone to the site of the breakwater (marked out in the sound by a line of buoys) were of a peculiar construction. They had two railways laid along them, parallel to each other, with openings in the stern, to admit the trucks laden with stones. These were wheeled from the quarry to the quay, thence to the openings in the vessel, and along the rails laid down in it, until both these lines of rail were filled with trucks. The vessel then proceeded on its way, bearing its load of trucks and stones, and, on reaching the breakwater, each truck was wheeled to the opening, where by machinery it was overset, and the stones cast into the sea. Fig. 232 shows the stern of the vessel, when loaded, with the ports up or closed; Fig. 233 shows

[merged small][ocr errors][graphic]

the stern of the vessel in the act of depositing the stones. The runner being hooked to the forepart of the truck, raises it up, and tips the stone overboard. By these means a cargo of sixty or eighty tons could thus be discharged in an hour.

A breakwater was thus formed, having a centre 3,000 feet long, and two arms, or bends, each 1,050 feet long, inclining towards the land. At the extremity of the western arm a circular foundation was prepared, on which a lighthouse has been placed. The entrance into the harbour on this western side is the principal entrance for shipping: it is about half a mile wide, and at low-water spring-tides the depth of water varies from seven to nine fathoms. The eastern entrance is of about the same width, but the depth of water is not so great, being about six or seven fathoms. The outer slope of the breakwater below the line of low-water was formed by the sea, and proves to be from three to four feet horizontal to one of perpendicular; from the low-water line upwards it is five to one. The inner slope is two feet horizontal to one perpendicular, from the base to the top, which is two feet above high-water springtides. When the action of the sea had formed its own slope, and had wedged together and settled the great mass of materials which forms the breakwater, and when no further movement was apparent, but the whole appeared consolidated together, then the

slope towards the sea was cased with regular courses of masonry, dowelled, joggled, dove-tailed, and cramped together; the diving-bell being brought into requisition for placing the lower courses, which were of granite, and were laid horizontally on their natural beds, and dove-tailed, lewised, and bolted together.

The Plymouth breakwater is capable of affording secure and convenient anchorage to a fleet of twentyfive or thirty sail of the line; and the additional advantage of a plentiful supply of fresh water is afforded by the construction of a reservoir above Bouvisand Bay, capable of containing from ten to twelve thousand tons, or a quantity sufficient to water fifty sail of the line. This water is brought in pipes to Steddon Point, opposite the anchorage, where a jetty is thrown out, from which the water descends through the pipes to the ships' boats. The whole expense of this valuable arrangement was about 16,000/.

In the construction of the Plymouth breakwater, experience had been gained by the failure of a previous attempt made on the French coast at Cherbourg. Under the direction of the French government, M. de Cessart prepared a plan for a barrier in the middle of the sea, and in front of that roadstead; but, unfortunately, he adopted, as the only mode of producing smooth water, the idea of a number of large masses of a conical form, touching each other at their base, but separating upwards, and leaving alternate openings and points of resistance, which, it was thought, would effectually break down and interrupt the waves entering the harbour. It was proposed to construct these conical caissons of wood, the number of which, to cover the destined extent of 2,000 toises, would amount to 90, causing a total expense of 32,400,000 livres for the whole. The number was afterwards reduced to 64, and the estimated time for completing them was thirteen years. Each cone was to be 150 feet diameter at the base, and 60 feet diameter at the top, and from 60 to 70 feet in height; the depth of water at spring tides, in the line in which they were intended to be sunk, varying from about 56 to 70 feet. Within the exterior cone was an interior and concentric one, bound together by beams of wood. The frame of each cone was composed of 80 large upright beams, 24 feet long, and 1 foot square. On these were erected 80 more, of 14 feet in length, making in all 320 large uprights. The machine was then planked, hooped, and firmly fixed together with iron bolts. The cones were to be sunk empty, and without bottoms, and were to be filled afterwards. On the 6th of June, 1784, the first cone was floated off, and sunk, and, on the 7th July following, a second, in the presence of ten thousand spectators; but before the cavity of the latter could be filled wil h stones, a storm in August, continuing five days, entirely demolished the upper part of the cone. The quantity of stones sunk that summer within the cavities of the two cones, outside their bases, and in the intermediate space, amounted to about 65,000 tons. In 1785, three more cones were sunk, and in the following year, five more. but the storms of winter carried away the upper parts of those five. Three were sunk in 1788; but these met with the same fate, so that government, in disgust at the delay and expense, sold the three cones then on the building-slips for whatever they would feteh. The array of persons employed on this undertaking was enormous. M. de Cessart, in order to make, and sink, and fill five cones a-year, found it necessary to have 250 carpenters, 30 blacksmiths, 200 stonehewers, 200 masons, and 520 general labourers. In the whole operation from first to last, there were employed from 1,200 to 1,500 artiticers and labourers, and to these were added about three thousand soldiers, for a body of troops had been marched to Cherbourg on the commencement of the undertaking, that there might be no lack of labourers to carry it into effect. This affords a remarkable contrast to the small establishment employed to carry on the Plymouth breakwater. Here there were the following persons:—

Persons.
A superintendent and proper officers

and clerks, to keep and control the
accounts 10

Warrant-officers and masters of the ten
stone vessels, in the immediate em-
ploy of the public 21

Seamen and boys to navigate these
vessels 90

Seamen employed in the superintend-
ent's vessel, the light vessel, boats'
crews, &c 45

Masons, blacksmiths, carpenters, sail-
makers, employed at Orestou . . 39

In the immediate pay of Govern-
ment 205

Saamen employed in the contractors'

vessels 170

Quarrymen, labourers, &c. employed
at Oreston by the contractors . . 300

675 The engineer of the Plymouth breakwater was Mr. Rennie, who did not live to carry through the whole of his undertaking; the lighthouse on the western extremity having been constructed from his designs by Messrs. Walker and Burgess. Among the plans rcjeoted by Government at the time that his was adopted, was one for a floating breakwater, composed of triangular or prismatic floats of wood, held together by iron chains. These might be extended across the whole sound, because they would allow a great part of the tide to pass through them, while the whole water-way below would be left clear. Sufficient intervals were to be left between the rows of floats, as well as the contiguous floats, to allow of ships shaping their course between them; and it was not thought likely that, in the event of a ship striking against, or even running over, one of these breakwaters, it would occasion any material injury to either. A floating breakwater, on a somewhat similar plan, has since been made the subject of a patent, and its practical application undertaken by a joint-stock company.

Fig. 234.

[graphic]

A patent was taken out in 1848 by Mr. Beardmorc, for an invention designed to facilitate the construction of breakwaters and other submarine works. It consists in the employment of a caisson or enclosure, constructed so as to float, with a portion of the structure built therein, to the spot where the breakwater is to be placed, and to constitute a part of the permanent work, which may be proceeded with to completion, with more expedition and convenience, and less liability to damage, than is usually experienced in such structures. The caisson consists of wrought-iron plate bottom, sides, and ends, and occasional transverse bulk-heads, strengthened by ribs, and firmly connected together, so as to withstand pressure in every direction; the whole being so bonded together as to constitute one entire frame, of great strength, solidity, and power of resisting strains. When sunk, with its enclosed masonry, it would at once form a solid foundation and a material part of the permanent work. A transverse section of one of these caissons, with its sides filled in with stones, is shown at Fig. 234.

BREAST-WHEEL. [See Hydratjlics.]

BREWING. [See Beer.]

BRICK. A building material, known at a very early period of the world's history, formed of tempered clay, hardened either by exposure to the sun's rays, or to the heat of a furnace. Bricks were used in the building of Babel, and it would appear that they were burnt bricks. (" Let us make brick, and burn them throughly. And they had brick for stone, and slime had they for mortar." Gen. xi. 3.) Also in the walls of Babylon, where the clay thrown out of the trench surrounding the city, supplied the material; and especially in the pyramids and other buildings of Egypt, where their manufacture gave employment to a vast number of persons, and at last became important enough to be undertaken by the state. Thus the public purchased of the government, and private individuals were forbidden to engage in the manufacture, or to use any bricks to which the government stamp was not affixed. The brick-makers worked in gangs, under the superintendence of overseers and task-masters; the clay was worked up with chopped straw, and the bricks prepared from it were dried in the sun. The employment was laborious, and the task-masters were as exacting as in later times. (Exod. v. 6—19.) The principal pyramids of Egypt are built of stone, but several of the smaller are of brick, as that of Howara, which is constructed of crnde bricks, containing chopped straw. These bricks measure 17£ inches by 8$ inches, and arc 5 5 inches thick. In some cases the bricks contain not only straw, but pieces of broken pottery and stone, and are very irregular in size. A brick pyramid about ten leagues from Cairo, is supposed to be that mentioned by Herodotus, as having once borne the following inscription: "Disparage me not, by comparing me with pyramids made of stone:

« السابقةمتابعة »