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with which they were personally conversant, and the plan has been kept up with spirit to the present time.” The specimens of material articles which our author had for his use were contributed partly by individual members, and partly by the liberality of other societies and public bodies. Engravings are given in the volume to supply the place of the specimens.

The subjects handled by Mr. Aikin are eleven in number, viz., Pottery; Limestone, and Calcareous Cements; Gypsum and its Uses; Furs and the Fur Trade; Felting and Hat-making ; Bone; Horn, Tortoiseshell, and Whalebone; The Antiquarian History of Iron; The Metallurgical History of Iron; Engraving and Etching ; and Paper. “If the present volume should prove acceptable to the public, it is the Author's intention to add to it a second, containing Illustrations on the following subjects :-Coals; Fuel and Fireplaces ; Artificial Light from the combustion of solids, liquids, and gases ; Silk and Weaving; Timber and Ornamental Woods; Detergent Substances ; Common Salt; Vegetable Fibre; Saccharine Substances; Tanning and Leather-dressing; and the Ceralia and Corn-mills."

Mr. Aikin had better lose no time in putting the manuscript for the second volume into the hands of the printer; for there need be no doubt of the one before us proving acceptable to many readers. It is a very attractive work as well as designed to be useful. It contains a great deal of knowledge conveyed in a pleasing and an earnest style. It exhibits the results of extensive reading and very considerable learning, antiquarian and also scientific. multitude of curious econonomical facts are brought together in a clear and cogent order; and be the reader a humble mechanic, or a person who has leisure to cultivate his mind within the domain of either the arts or manufactures, he will derive benefit from the book. It is suggestive even much beyond the branches or subjects handled; lending a scientific dignity to the most ordinary crafts, and directing the mind to philosophical principles that may be applied in every trade and to the humblest kinds of business.

It will be seen from the mere enumeration of the subjects selected by Mr. Aikin that, however commonplace they may at first appear, there has been a judicious attention to variety. In some, chemical processes change the entire shape and consistency of natural productions ; in others, these productions retain their original nature, but have to submit to operations which change their form ; while others, again, are either pure arts or pure manufactures. In all, the history of civilization is more or less illustrated; while the progress of commerce is very distinctly indicated in several.

We have intimated that the manner of our author's treatment, the rich facts which he has collected, and the science or philosophical principles which his illustrations teach, lend to every one of his

A great

topics dignity and attraction. We do not well know to which of the papers we should repair with the view of most deeply interesting the reader or exemplifying Mr. Aikin's manner and matter. But seeing that to the popular inquirer there must be a good deal that is novel as well as at all times striking in each of the essays, there is the less occasion for anxious selection.

Pottery, for example, opens a wide field. It presents an ancient as well as a modern history. The manufacture of clay into bricks, and into urns and domestic utensils, involves physical and chemical principles that are worthy of much consideration. The manipulations and machinery employed in the different manufactures of earthenware are obviously important features. And then what is to be said of the connexion of the fine arts and correct taste with pottery? But to attend for a moment to what may be deemed the humblest branch, as respects skill, of the manufactures from clay : This is historical,

“In England, from the time of the Romans to the eleventh century, there is no evidence of the use of bricks as a material for building. But about that time the abbey of St. Albans was erected, and bricks were employed in its construction; the probability however is, that these materials were obtained from the ruins of the adjacent Roman town of Verulam. St. Botolph's Priory, at Colchester, was founded thirty years after the abbey of St. Albans, and of this building brick is the principal material. The form of these bricks might justify a suspicion that these likewise were taken from some Roman building; but it is just as likely that the Roman bricks would furnish the model for the earliest made English bricks, and an additional reason for this may be derived from the name wall tile having long preceded that of brick. King's Hall, Cambridge, was built of bricks in the reign of Edward the Third, at which time it appears that the price of them was from 6s. to 6s. 1d. a thousand. The use of this material seems, however, to have been for some centuries almost wholly confined to public buildings and large mansions, for Holinshed, in the introduction of his · History of Queen Elizabeth,' enumerating the materials employed at that time for building houses, omits all mention of brick.

“ Till lately, bricks appear to have been made in this country in a very rude manner. The clay was dug in the autumn, and exposed to the winter frosts to mellow ; it was then mixed, or not, with coal ashes, and tempered by being trodden by horses or men, and was afterwards moulded, without it being considered necessary to take out the stones. The bricks were burnt in kilns or in clamps: the former was the original mode, the latter having been resorted to from motives of economy. When clamps began to be employed I do not know; but they are mentioned in an act of parliament passed in 1726, and therefore were in use prior to that date."

A raw brick, we are told, “ weighs between 6 and 7 lbs. ; when ready for the clamp it has lost about 1 lb. of water by evaporation.

A first-rate moulder has been known to deliver from 10,000 to 11,000 bricks in the course of a long summer's day, but the average produce is not much more than half this number." We shall here quote a paragraph from the last essay in the volume, viz., on Paper, another pure manufacture. "If," says Mr. Aikin, " we take any of the white, smooth, soft papers, whether used for writing on, such as the so called Bath Post, or for printing on, and burn a slip of it, we shall find that the black coal which it leaves, on being heated just on the outer edge of the flame of a candle, assumes a mealy white appearance, and on being laid on the tongue has exactly the favour of an earthy alkaline sulphuret. It is therefore highly probable that such papers contain gypsum or sulphate of barytes, added both for the purpose of increasing their weight and their compactness. The consequence of this adulteration is great brittleness of the paper and a peculiar creaking noise in writing on it, arising from the friction of the earthy particles, which soon wear out the point of the pen."

The essay on Furs and the Fur-trade gives us a very able and wellinvestigated account of the uses of furs in ancient times, of the great sources of supply, then and now, and of the English commerce and manufactures in these sorts of skins. We open almost at random to find a few short passages in the paper under consideration :

“ The ermine is a small animal, and therefore the number of such skins employed to line the full robes and mantles of princes and nobles, when furs were in their highest fashion and esteem, may readily be conceived, as well as the enormous expense attached to the indulgence of this taste. In the account of Stephen de la Fontaine, silversmith and master of the robes to Louis IX. of France in 1251, is the following entry : 'For three pieces and a half of velvet in grain, to make a surcoat, a dress-mantle and a hat lined with ermines for the king against the feast of the star. For the said surcoat a fur lining of 346 ermines, for the sleeves and wristbands 60, for the frock 336. In all, 742 ermines for a single dress.

“ The four noble furs of those ages were the sable, the ermine, the vair, and the gris. The three former of these represented the three fur colours admitted into their armorial bearings. Every one at all acquainted with heraldry knows that ermine is represented by a white ground with black somewhat lengthened spots. These were intended to designate the blacktipped tails of the animals, the skins being sewn together either with the tails on, or the tails were first cut off and afterwards sewn in rows upon the skins, sometimes alone, sometimes with a little wad of black lambskin on each side of the tail. This arrangement is so obvious, I may say so natural, that it would not have been worth a remark in this place, except for its connexion with the science of heraldry."

England does not appear ever to have produced, unless it has been in the most barbarous times, furs sufficient for its own consumption. But in consequence of the discovery, in 1553, of the passage by sca to the northern coast of European Russia, and again of discoveries in North America, and of Hudson's Bay, London became one of the centres of the fur-trade. Our country, however, furnishes but a small amount of skins, and hardly any that are peculiar :

One fur, and one only, is peculiar to England, namely, the silvertipped rabbit of Lincolnshire. This fur is a dark or lighter gray, mixed with longer hairs tipped with white. It is little used in this country, but is readily purchased abroad, especially in Russia and China. In sssorting it for these markets, it is, however, necessary to be careful with respect to the colour, for while the Russian will eagerly purchase the dark-coloured skins he makes no account of the gray ones. The Chinese are equally fastidious, but their taste happens to be the reverse of the Russians. Thus the fur-merchant, to dispose of his commodities to the best advantage, must be familiar with the caprices of fashion on the other side of the globe ; I

say the caprices, because a few years ago none but dark skins were saleable in China.”

The day has been when the use of furs was forbidden in this country, unless by persons whose income was at least £100 a year. American furs come in their raw state, that is, merely dried.“ They are dressed here by treading them with refuse butter, which makes the skin supple, and not liable to break or tear ; but as this cannot be done without also greasing the hairs, it is necessary after treading to turn them for some time in a revolving barrel set on the inside with spikes, and containing chalk, gypsum, or saw-dust, which absorbs the superfluous grease.” When the whole earth has become inhabited, and subject to a settled population, furs must grow scarcer; unless, indeed, as the Anglo-Saxons did, people be content to make use of the skins of cats and lambs in the list of their robes and ornaments.

The paper on Felting and Hat-making thus opens :

“ The use of hats, that is of caps with brims to them, is of very ancient date. Among the Greeks, the Dorian tribes, probably as early as the age of Homer, were characterised by the broad-brimmed hats which they wore when on a journey. The same custom prevailed among the Athenians, as is evident from some of the equestrian figures in the Elgin marbles. The Romans appear in general to have used no covering for the head except a corner of the toga or upper garment; but at sacrifices and festivals they wore a bonnet or cap, and, this being permitted only to free men, part of the ceremony of manu

numitting a slave consisted in putting one of these caps on his head. But on a journey, the Romans were accustomed to wear a hat called petasus, with a margin wide enough to shade their faces from the sun.

“ In the middle ages the bonnet, or cap with a narrow margin in front, appears to have been in use among the laity while ecclesiastics wore hoods or cowis : but Pope Innocent IV. in the thirteenth century allowed to the cardinals the use of scarlet hats. About the year 1440 the use of hats by persons on a journey appears to have been introduced in France, and soon became common in that country, whence probably it spread to the other European states. The

cap of the ancients was certainly made of wool, and this, as well as the hat, was probably knit. I do not know when felt was introduced as a material for hats, but it is stated that the hat worn by Charles VII. of France, on occasion of his triumphant entry into Rouen in 1440, was of felt."

The origin of felt does not afford any clear or decided records ; but the following facts are consistent with our school-age experiments and marvel :

“If we take a common hair of the head and, holding it fast by the root end, draw it gently between the finger and thumb, it passes through smoothly and with hardly any sensible resistance or interruption; whereas if we reverse the motion, holding the hair by the point and drawing it from point to root, a very sensible tremulous resistance will be experienced, accompanied by a creaking kind of sound. Again, if we place a hair loose, lengthways between the finger and thumb, and then by alternately bending and extending them give them a backward and forward movement, the hair will be put in motion; and this motion will be always from root to point whether the root be in one or the opposite position with respect to the two rubbing surfaces. A fibre of wool likewise in similar circumstances always moves in one direction. Every schoolboy knows that an ear of barley if put within his sleeve at the wrist soon travels upward to his armpit, and that a single awn of barley when rubbed in the direction of its length between the finger and thumb will move only one way, that is from root to point. The awn of barley is visibly jagged at the edges like a saw, the teeth pointing obliquely upwards, and this particular conformation is manifestly the reason why it is capable of motion in one direction but not in the contrary. A similar structure might be expected in hair and wool; and although this is but imperfectly shown by common microscopes, yet the greatly improved instruments of the present day render this structure quite obvious, as is evident from the accompanying figures, for which I am indebted to the graphic skill and accuracy of Mr. C. Varley."

We cannot conveniently insert the illustrative figures mentioned ; but we may add a few clearly-stated particulars relative to the formation of felt:

“Wool in the yolk, that is, with the natural grease of the sheep adhering to it, will not felt; because in this state the asperities of the fibre are filled and smoothed over, just in the same manner as oil diminishes and almost destroys the action of the finest files. But fine wool that has been properly scoured has so strong a tendency to mat or intertwist or felt-for all these words only imply various degrees of the same thing--that it cannot be spun into an even thread without being previously oiled sufficiently to

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