This feast in honour of the dead, called silicerniunz by the Romans, is given almost over the whole world, and is a rite still retained in Britain. Certain tribes of Ame rican savages preserve the remains of the deceased in the same way as the Kookies, until a certain time of the year.
The bodies of deceased Birmans are burnt ; but as the ceremony is attended with great expellee, this honour is not conferred on the poor. Funerals are solemnized with much religious parade and semblance of grief in the king dom of Ava. The corpse, preceded by women chaunt ing a dirge, is carried in slow procession on a bier on men's shoulders, and attended by the relatives in mourn ing. When placed on a pile, which is about six or eight feet high, formed of billets of dried wood laid across, with interstices to admit the air and promote the confla gration, the priests walk around, reciting prayers to their deity. When the fire reaches the body, it is quickly re duced to ashes ; and the bones, being afterwards collect ed, are deposited in a grave. The bodies of the chief ecclesiastic of a province, and of persons of exalted sta tion, are embalmed, and lie in state in some religious edifice six weeks before they are committed to the pile.
Cremation of the dead is practised by the natives of New Holland, a race which ranks lowest in the scale of mankind. The surviving husband constructs a pile to consume the belly of his departed wife : he collects her ashes, and, depositing them in the earth, erects a rude and simple memorial of her on the spot. See Herodotus, 0.
On CATOPTRIC BURNING INSTRUMENTS It appears, from the authority of Plutarch, that the amcients were acquainted with the power of concave mirrors to concentrate the solar rays, and to burn substances placed in their focus ; and there is every reason to believe, that it was by a contrivance of this kind that the vestal fires were rekindled. This method, how ever, of producing an intense heat from the solar rays, can be practised only at short distances, and is complete ly incapable of producing those tremendous effects at a distance which Archimedes is said to have exhibited at the siege of Syracuse.
The concurring testimonies of several ancient authors* sufficiently establish the general fact, that by a combina tion of mirrors, constructed by Archimedes, the Roman fleet was either partly or wholly consumed. By means of a similar apparatus, as we are informed by Zonaras, (Annal. lib. xiv. p. 55.) Proclus destroyed the Gothic ships in the harbour of Constantinople, in order to protect his benefactor, Anastasius, against the bold attempt of Vitalian.
The credibility of these statements has been seriously questioned by many modern mathematicians of the high est eminence, and the exploits of Archimedes at Syra cuse have been confidently ranked among the fables of antiquity. All this scepticism, however, seems to have been founded on the supposition, that the Syraeusan phi losopher employed concave mirrors ; for if we suppose, along with Kircher and Buffon, that Archimedes em ployed a combination of plain mirrors, and if we make some allowance for the exaggeration of ancient authors, we must admit it as a fact well authenticated, and in no respect contradicted by the principles of optics, that A rchimides constructed a burning machine, by which he set fire to the Roman fleet at a considerable distance. When the rays of the sun are reflected from a plain mir ror upon any object, the space occupied by the reflected light is always greater than the surface of the mirror, and this space increases with the distance of the object. The heat which is lost by reflection does not much ex ceed one-half of the direct heat of tl.e solar rays ; so that two plain mirrors, which reflect the stm's light upon an object moderately distant, evil; produce a degree of heat nearly equal to the direct heat of the sun. By increasing, therefore, the number of mirrors, the reflected heat ofthe sun may be increased to any assignable magnitude. If the distance (Attie object is increased, the space occupied by the reflected rays from each mirror will also he in creased ; and, in proportion to this augmentation, the in tensity of the heat will be (Unfinished ; but this diminution of the heat may be compensated by increasing the num ber of the mirrors. Hence it is possible, theoretically speaking, to produce any degree of heat at any given dis tance. In practice, however, the distance at ‘% hick com bustion may be effected is limited by several causes. Wbile the reflected rays pass through the atmosp'iere. their force is considerably diminished by the density of the medium ; and even when the plain mirrors are form ed with the utmost care, they are still by no means free from irregularities on their surface. The angular devia tion produced by these irregularities increases with the distance at which the reflected rays arc received ; and at the distance of a mile, the reflected light, instead of form ing one large image, would be separated into various detached portions.