tyro in arithmetic must at once see that a year and a half, or forty-two current months as the term is now understood, instead of containing only 1,260 days, would contain—

42 months 3 years, × 365 = 1,278 days.

These three expressions, then, being clearly coincident, we have as it were, such a three-fold cord as cannot be easily broken. Mr. Fleming next proceeds to prove from Scripture, that days are in prophetical language employed to signify years, and having established this point, endeavors to fix the period at which the reign of Antichrist may be said to have commenced, following up the question in these words—

"It is plain from Rev. xvii. 10, that the Imperial Government was the Regnant Head of the Roman beast, at the time of the vision; we have only the two following heads to consider, as to their rise and duration. Let these things, therefore, be minded here.

"1. That the seventh head, or king of Rome, whose character is, that he was immediately to succeed to the imperial government, and to continue but a short space, could be no other than that of the kingdom of the Ostro-Goths in Italy.

"For it is plain that the imperial dignity was extinguished in Italy, and in the western parts of the empire, by Odoacer, the king of the Heruli, who forced Augustulus, the last sprig of an emperor, to abdicate his throne and power, in the year 475 or 476, as others say. And though this Odoacer was soon destroyed by Theodoric, the king of the Ostro-Goths; yet the same form of regal government was continued by Theodoric and his successors. And though this kingdom continued for nearly eighty years, reckoning from Odoacer to Teias, yet the angel might justly call this a short time: for so it was, if compared either with the preceding imperial or succeeding papal government: And surely this kingdom was sufficient to constitute a new head of the Roman people, seeing Rome and Italy was subjected entirely to those Gothish kings, and that they not only acted with the same authority that the emperors had used before (excepting that they abstained from that title by a special providence, that they might not be confounded with that government,) but were owned by the senate and people of Rome as their superiors, yea, by the emperors of the east also.

"2.

We may conclude that the last head of the beast, which is the Papal, did arise either immediately upon the extirpation of the Gothish kingdom, or some time after; but it could not rise to its power immediately after, seeing Justinian did by the conquest of Italy revive the imperial government again there, which by that means was healed after the deadly wound which the Heruli and the Goths had given it. Though, I confess, Justinian's conquests of Italy laid a foundation for the pope's rise; and paved the way for his advancement, both by the penal and sanguinary laws which he made against all those that dissented from the Romish Church, and by the confusion that followed upon Narses, his bringing in the Lombards. For, during the struggles of them and the Exarchat, the pope played his game so, that the emperor Phocas found it his interest to engage him to his party, by giving him the title of supreme and universal bishop.

"Therefore we may justly reckon that the papal head took its first rise from that remarkable year 606; when Phocas did, in a manner, devolve the government of the West upon him, by giving him the title of universal bishop. From which period, if we date the 1260 years, they lead us down to the year 1866, which is 1848, according to prophetical calculation. Or, if a bare title of this sort be not thought sufficient to constitute the Pope head of the beast, we may reckon this two years later―viz., from the year 608, when Boniface the IVth. did first publicly authorize idolatry by dedicating the Pantheon to the worship of the Virgin Mary and all the saints."

It ought in justice to be added, that as Mr. Fleming reckons that the full rise of Antichrist did not take place till 758, when the pope was first invested with independent temporal authority, he supposes it will continue to exist till the year 2,000, though in a greatly weakened state.

To those who are curious in watching the signs of the times, we would strongly recommend this little volume, so opportunely reprinted for their convenience. Whether its author be right or wrong, he was evidently a man of deep thought, extensive knowledge, and sterling common sense.

PHOTOGRAPHY.

Two centuries ago, a philosopher of Naples, Giovanni Battista Porta, discovered that if a very small hole be pierced in the window-shutter of a room completely darkened in other respects: or better still, if the aperture be perforated in a thin metallic plate applied to the shutter; all the exterior objects from which rays can enter through this opening will be represented on the opposite wall; in dimensions enlarged or diminished according to the distance. He found also that even with this imperfect apparatus, throughout a large extent of the picture, objects were painted in their natural colors, and with considerable truth of linear perspective. A short time afterwards Porta found that it was not necessary to have the opening very small, thus limiting the view, but that if the perforation were covered with a lens or convex glass, it might be of any dimension. He remarked also the great improvement thus produced in the delineation. The images passing through the simple medium of the hole were without distinctness of position, intensity of color, or neatness of outline. On the contrary, with the lens the mimic forms rivalled the vivacity and strength of nature herself, the focal distances being properly adjusted. It is well known that all these discoveries of Porta have become truly astonishing in precision of detail and strength of coloring since the art of constructing achromatic glasses has been brought to its present perfection. Formerly a simple lens composed of one kind of glass only, and consequently acting with as many separate focuses as there are colors in the undecomposed white ray, transmitted a comparatively indistinct image of objects. Now that we employ achromatic glasses which combine all the incident rays in one focus, and that a periscopic construction of the apparatus likewise has been adopted, great perfection has been given of its effects.

Porta constructed also a portable dark chamber, or camera obscura. These chambers were usually formed like a box with a tube furnished with the proper lenses at one end; and at the other a screen of white paper, or some prepared substance, occupied the focus, upon which the images of external objects were received. The Neapolitan philosopher proposed his simple arrangements for the benefit of those who had not been taught drawing. According to him, nothing else was required in order to obtain

the most perfect transcripts of nature than merely to trace carefully the outline of the focal image.

These anticipations of Porta have not been completely realized. Painters and draughtsmen, those particularly who execute large views for panoramas, dioramas, and theatres, have indeed still recourse to the camera. They, however, employ it merely to group objects or to trace their outline and arrangements.

Long ago, the chemists had succeeded in forming a solution of silver in muriatic acid. This compound, which assumes the appearance of a white salt, they called lunar or caustic silver. This salt possessed the remarkable property of becoming black by light, and of blackening more or less rapidly in proportion to the intensity of the incident rays. Cover a sheet of paper with a wash of lunar caustic, or, as we say at present, with a wash of chloride of silver; form upon this, by means of a lens the image of an object; the shaded parts of the image, or those upon which no light falls, will remain white; the portions, on the other hand, strongly illuminated, will become completely black; the demi-tints will be represented by grays more or less dark. This monochrome, in short, will be the reverse of the real object as respects the lights and shadows.

Again, if any engraving be placed on a sheet of paper moistened with a solution of chloride of silver, and both be exposed to the solar light, the engraving being uppermost, the dark lines of the latter will intercept the rays, and the corresponding portions of the paper below will retain their original color. In those parts, on the contrary, which lie immediately under the lights in the engraving, the solar rays, acting through the imperfect transparency of the print, will blacken the chloride wash. The necessary consequence of this operation will be a copy of the engraving, correct in its outlines, but reversed in its effects, the lights being reproduced in shadows, and the shadows in lights.

These applications of this curious property of the chloride of silver, one would think, might have readily occurred to the first discoverers of the substance, or to their early successors, who devoted more attention to practical results. Not so, however, was the case. We must descend to the first years of the present century before we detect even the beginnings of the photographic art.

About this time a Frenchman, named Charles, in his lectures, made use of a prepared paper to produce silhouettes, or black profiles, by the action of light. Charles died without describing the preparation which he employed. As the historian of science, under the pain of falling into inextricable confusion, is not authorised to proceed, except upon printed and authentic documents, it is no more than justice to assign to Wedgewood, the celebrated porcelain manufacturer and inventor of the pyrometer for high temperatures, the first application of this new art.

The memoir of Wedgewood appeared in 1802 in the number for June of the Journal of the Royal Institution of Great Britain. The author there proposes by means of skins, or with paper steeped or washed in chloride or nitrate of silver, to copy paintings on glass as in the windows of churches, and also engravings. "The images formed by means of the camera obscura," we quote faithfully a passage from the article, "have been found to be too faint to produce, in any moderate time, an effect upon the nitrate of silver."

The commentator upon Wedgewood's experiments, the illustrious Sir Humphry Davy, does not contradict the assertion relative to the images of the camera. He merely adds, as to his own experiments, that he has accomplished the copying of very small objects by the solar microscope, but only at a short distance from the lens.

Finally, neither Wedgewood nor Sir H. Davy discovered how, the operation once finished, we were to give it permanence, or, prevent the pictures from becoming black by the action of light. It thence resulted that the copies which they had obtained could not be examined by day-light, for in a very short time they became uniformly black, and all lineaments of the previous objects disappeared. What was this in reality but to produce imagery so evanescent, that only a furtive glance could be cast upon the work, and that by the light of a lamp? The whole would have vanished in a few seconds if these delineations had been examined in day-light.

We now arrive at the researches of Messrs. Niepce and Daguerre. The late M. Niepce was a country gentleman, who lived on his property near Châlons, on the Saône. The Photographic researches of M. Niepce appear to have been begun só