March 20. known how to regulate and employ for his own

purposes.

The ocelot resembles, in form, the other animals of the cat kind. In size it may be accounted nearly a medium between the tiger and the domestic cat. It is in length about four feet, and in height, about two feet and a half. Its fkin is elegantly variegated by a great number of oblong marbled stripes. Its general colour is a bright tawny. A black stripe extends along the top of the back from head to tail; its forehead is spotted with black, as are also its legs; its fhoulders, sides, and rump, are beautifully marbled with long stripes of black, forming oval figures, filled in the middle with small black spots. Its tail is singularly marked with large spots, and black at the end. The colours of the female are lefs vivid than those of the male; neither is it so beautifully marked.

It is a native of South America; inhabits Mexico and Brazil; is very voracious and timid; but seldom attacks men. It is afraid of dogs; and when pur

sued flies to the woods.

It lives chiefly in the mountains, and conceals itself among the leaves of trees, from whence it darts upon such animals as come within its reach. It sometimes extends itself along the boughs, as if it were dead, till monkies, tempted by their natural curiosity, approach within its reach. It is said to prefer the blood of animals to their flesh.

This creature is among the most savage and untameable of all the savage tribe to which it belongs.

No usage can make it gentle. It is perpetually restlefs, and seeking what it may devour. Those which have been shown in Europe, therefore, must always be kept secured within a strong cage, as the only means of guarding against mischief by them. A male and female ocelot were brought from France some years ago, which had been taken when very young. At the age of three months they became so strong and fierce, as to kill a bitch that was given them for a nurse. When a live cat was thrown to them, they sucked its blood, but would not taste its flesh. The male seemed to have a great superiority over the female, as he never allowed her to partake till his own appetite was satisfied.

Like all the larger animals of the cat kind, the ocelot produces but a small number at a time. The two above mentioned, were the only young ones found with the mother; which was killed at the time they were taken; and makes it probable they bring forth only that number.

DISQUISITIONS CONCERNING THE MODE OF MAKING BRICKS AMONG THE ROMANS.

Continued from p. 66.

GLASS makers are at present subjected to a very great expence by the breaking of their crucibles, which might be effectually obviated by employing a composition of the same nature with that above described. In the manufacture of glafs it is necessary to have very large crucibles for containing the mel

ted matter in great quantities.

These crucibles

very difficult to

must consist of materials that are melt, and that are at the same time of a very compact texture. The only substance they have hitherto found, which pofsefses these proper→ ties, is a very pure kind of clay. This they reduce to a very fine powder; soak it in water till it becomes as soft as pap; it is then kneaded up with great care, into small pastils, of about half a pound weight each, which are allowed to dry till: they become of a proper consistence. The workman then forms his crucible, by beginning at the bottom: this is done by succefsive thin layers, worked dexterously one above the other, allowing the preceding one to dry a little before the next layer is applied. It is impossible to convey an adequate idea by words of the manner in which these layers are applied; but long practice has taught the men a manner of applying them, that is as efficacious as can be imagined, for closing the pores which are. gradually produced by shrinking in drying, by succefsively prefsing, from time to time, all the parts of the crucible, in every stage of the operation, from the time that the clay is first applied quite soft, till it has attained a very considerable degree of hardnefs; yet notwithstanding all this attention and care, it frequently happens that these crucibles are incapable of containing the melted glass from the begin ning, or are bursted the very first time the fire is aplied to them. But if a considerable proportion of the clay were first burnt, and then powdered before it was mixed with the native clay, the composition would

fhrink much lefs in drying, and would, by consequence, be much lefs subject to be damaged by small fifsures, or to burst upon the application of the fire.

1

These very glass men, although they have not thought of adopting this improvement, do nevertheless adopt a practice exactly founded on the same principles here recommended, in another branch of their business. It is necessary for them to have the sides of their furnace coated with some kind of material that is able to resist, for a very long time, the action of their very intense fire. This they find is best effected by a kind of bricks formed of the same kind of clay with their crucibles; but as it would have been a work of very great expence to work these bricks up in the same manner they do the crucibles, they have thought of abridging the labour, by mixing some dry powder with the clay paste; and the powder they employ for this purpose is the old crucibles themselves, after they have been baked in the furnaces sufficiently, and when they are no longer fit for service in that way. These old crucibles are then broken into small pieces, which are afterwards grinded in a mill, like a sugar baker's mill, till it is reduced to a grofs kind of powder, which is intimately mixed with the clay paste in due proportion, and then formed into large bricks, about two feet in length and one foot in breadth, which dry slowly without any cracks or fifsures, and when perfectly dry, are built into the furnace as occasion may require, where they remain, long, and perfectly resist the greatest heat that is ever applied to them, with out fhewing any tendency to vitrification.

It is probable that the old Roman bricks were formed, somewhat after the same manner, of clay alone, a part of which had been previously burnt and reduced to powder, to be mixed with the native clay, which would form a composition capable of bearing a fire sufficiently intense to reduce the whole to a stony state without vitrification. At any rate, it is certain, that by following this practice, we might form a kind of bricks that would be equally hard with the hardest native stone, and that would more effectually resist the imprefsions of the air, and vicifsitudes of weather, than almost any other stone, granite, perhaps alone, excepted.

Were a composition of this kind introduced into common use, it might be employed for many valuable purposes, not only in contributing to the durability of our buildings, but also in promoting the improvement of the fine arts; as I fhall perhaps endeavour to fhow in some future essay.

,

Roman bricks were of a much larger size than those of modern times. The reason of this smallness of size in our bricks is obvious for as we are not at liberty to apply a great heat to any part of them, lest the outside fhould be vitrified, should we attempt to make them large, the heart of each brick would be entirely raw and unbaked, so as to be much worse than they are when formed of the present size. But were we at liberty to employ a sufficient degree of heat to bake them to the heart, as could be safely done by adopting the plan suggested in the forego-. ing part of this essay, we might have bricks of any size that should be judged most convenient.