opinion of Pere Maimbourg, who, after the relation of the battle of Iconium, won by Frederick of Barbarossa, 1190, says, "What was chiefly wonderful after this battle, was the conqueror's sustaining little or no loss, which most people ascribed to the particular protection of St. Victor and St. George, names oftenest invoked in the Christian army, which many of them said they saw engaging at the head of the squadrons. Whether in reality there might be something in it extraordinary, which has often happened, as the Scriptures inform us; or whether, by often hearing of celestial squadrons appearing at the battle of Antioch in the first crusade, warm imaginations possessed with the belief, and penetrated with these ideas, formed new apparitions of their own, but sure it is, that one Louis Helfenstein, a gentleman of reputation, and far from a visionary, affirmed to the emperor, on his oath, and on the vow of a pilgrim devoted to the holy sepulchre and the crusade, that he often saw St. George charge at the head of the squadrons, and put the enemy to flight; which was afterwards confirmed by the Turks themselves, owning that they saw some troops in white charge in the first ranks in the Christian army, though there were really none of that livery. No one, I know, is bound (continues P. Maimbourg) to believe visions of this kind, subject for the most part to notorious illusion: but I know too, that an historian is not of his own authority, to reject them, especially when supported by such remarkable testi

Hist. Crusade, 1. 5.

mony.

And though he be at liberty to believe or not, yet he has no regret, by suppressing them, to deprive the reader of his liberty, when he meets with passages of this kind, of judging as he thinks fit." This reflection (says Bayle) from so celebrated an historian, not suspected of favouring the Hugonot incredulity, is a strong presumption on my side.

The abuse of presentiments has been carried to the very Scriptures. We are told, that the manner of Tamerlane giving his blessing to his two sons, by bowing down the head of the elder, and chucking the youngest under the chin, was a presage of the elevation of the latter in prejudice to the former, was grounded on the 48th chapter of Genesis, where Jacob is represented laying his right hand on the head of the younger, forseeing by inspiration that he would be the greater of the two. Meanwhile there is a difference between the two benedictions. The Tartar, wholly destitute of the knowledge of future events, did not diversify the motion of his hands, on purpose to establish a presage; and God never vouchsafing this knowledge to infidels, did not guide his hands in a particular manner to form a presage of what should befal his children ;--whereas Jacob, on the contrary, filled with the spirit of prophecy, whereby he saw the fortunes of his children, directed his words and actions according to this knowledge; by which means both became presages.

Presages, presentiments, and prodigies, might be multiplied ad infinitum. Whoever reads the Roman historians will be surprised at their number, and which frequently filled the people with the most

dreadful apprehensions. It must be confessed, that some of these seem altogether supernatural; while much the greater part only consist of some of the uncommon productions of nature, which superstition always attributed to a superior cause, and represented as the prognostications of some impending misfortunes. Of this class may be reckoned the appearance of two suns; the nights illuminated by rays of light; the views of fighting armies; swords and spears darting through the air; showers of milk, of blood, of stones, of ashes, or of fire; and the birth of monsters, of children, or of beasts who had two heads; or of infants who had some feature resembling those of the brute creation. These were all dreadful prodigies which filled the people with inexpressible astonishment, and the whole Roman empire with an extreme perplexity; and whatever unhappy event followed, repentance was sure to be either caused or predicted by them.

* Nothing is more easy than to account for these productions, which have no relation to any events, no more than comets, that may happen to follow them. The appearance of two suns has frequently happened in England, as well as in other places, and is only caused by the clouds being placed in such a situation as to reflect the image of that luminary; nocturnal fires, inflamed spears, fighting armies, were no more than what we call aurora borealis, northern lights, or inflamed vapours floating in the air; showers of stones, of ashes, or of fire, were no other than the effects of the eruptions of some volcano at a considerable distance. Showers of milk were only caused by some quality in the air condensing and giving a whitish colour to the water, etc.

CHAPTER XVI.

PHENOMENA OF METEORS, OPTIC DELUSIONS,

SPECTRA, ETC.

THE meteors known to the ancients were called Auurdes IIOo Bolides, Faces, Globi, etc. from particular differences in their shape and appearance, and sometimes under the general term of comets. In the Philosophical Transactions, they are called, indiscriminately, fire-balls, or fiery meteors ; and names of similar import have been applied to them in the different languages of Europe. The most material circumstances observed of such meteors may be brought under the following heads: 1. Their general appearance. 2. Their path. 3. Their shape or figure. 4. Their light and colour. 5. Their height. 6. The noise with which they are accompanied. 7. Their fire. . Duration, 9. Their velocity. Under these different heads meteors have been investigated by the scrutinizing of philosophy, and many superstitious notions, long entertained concerning them, entirely exploded. Meteoric phenomena, it has been demonstrated, all pro

ceed from one common cause- irregularity in the density of the atmosphere. When the atmospheric fluid is homogenous and of equal density, the rays of light pass without obstruction or alteration in their shape or direction; but when they enter from a rarer into a denser medium, they are refracted or bent out of their course; and this with greater or less effect according to the different degrees of density in the media, or the deviation of the ray from the perpendicular. If the second medium be very dense in proportion, the ray will be both refracted and reflected; and the object from which it proceeds, will assume a variety of grotesque and extraordinary shapes, and it will sometimes appear as in a reflection from a concave mirror, dilated in size, and changed in situation. The following striking effects are known to proceed from this simple cause.

The first is the mirage, seen in the desert of Africa. M. Monge, a member of the National Institute, accompanied the French army into Egypt. In the desert, between Alexandria and Cairo, the mirage of the blue sky was inverted, and so mingled with the sand below, as to impart to the desolate and arid wilderness an appearance of the most rich and beautiful country. They saw, in all directions, green islands, surrounded with extensive lakes of pure and transparent water. Nothing could be conceived more lovely and picturesque than this landscape. On the tranquil surface of the lakes, the trees and houses, with which the islands were covered, were strongly reflected with vivid hues, and the party hastened forward to enjoy the cool refreshments of shade and stream, which