A thorough test of the capabilities of such a telescope having been made with disappointing results by Professor E. S. HOLDEN upon his accession to the directorship of the observatory, the building has long since been relegated to humbler uses.

The topography represented in the cut is in some respects misleading, although it very well shows the open character of the surroundings. The observatory stands upon the crest of a hill, which slopes gently to the west, and more rapidly to the south and north, upon which latter side it descends to the shores of Lake Mendota, about a hundred feet below it.

The principal instruments of the observatory are the CLARK equatorial telescope of 395mm (sixteen inches) aperture, and the REPSOLD meridian-circle of 122 mm (five inches) aperture. The latter instrument is substantially similar in construction and appearance to the one illustrated at page 86, Vol. III, Publications of the Astronomical Society of the Pacific, and in the hands of the successive observers who have used it, has proved capable of furnishing results of the highest order of excellence, both in the determination of star places and in the investigation of stellar parallaxes.

In its optical parts the CLARK equatorial has shown itself an instrument of very superior quality, but in respect of mounting it lacks many of the conveniences of more recently constructed instruments. It is provided with a filar micrometer, doubleimage micrometer spectroscope, a ZOELLNER astro-photometer and a very complete set of oculars.

The small equatorial in the Students' Observatory, shown in the accompanying cut, has been provided with a modified LOEWY prism apparatus and employed in various researches requiring the simultaneous observation of stars situated in widely different parts of the heavens. This has required the construction of the peculiar type of dome there shown, with revolving semi-circular shutter. This shutter has proved in practice an excellent device, and may be recommended for general use in small domes.

Three astronomical clocks (employed in connection with the railway time-service), chronometers, a chronograph, an excellent universal instrument, and a considerable amount of subsidiary apparatus employed in instruction, supplement the equipment above described. To this there should be added the excellent Woodman Astronomical Library, comprising over five thousand

books and pamphlets, which are housed in the east wing of the observatory.

The scientific activity of the observatory has lain almost wholly along the lines of the older astronomy of precision, and the chief results of that activity are set forth in the ten volumes of its Publications.

MADISON, December, 1896.

SOME LUMINOUS APPEARANCES IN THE SKY.

By W. H. S. MONCK.

In Nature for March 28, 1896, appeared an account of a luminous appearance seen in the sky by Dr. BRAUNER, of Prague, on the thirteenth of that month. There were five streaks reaching from the western horizon towards the zenith, apparently not of very long duration. It was only about an hour after sunset, and Dr. BRAUNER ascribed them to some peculiar reflection in the upper regions of the atmosphere. This explanation, however, is not applicable to a similar phenomenon described by Mr. LYON BROWNE, of Shrewsbury, in Knowledge for April; for it was seen at 8" 30" on the 4th of March, and therefore a considerable time after sunset. It disappeared in the course of ten minutes. It also stretched from the western horizon towards the zenith. Mr. BROWNE thought it might be the zodiacal light, but this seems hardly probable; and the descriptions given do not closely resemble the aurora.

The hypothesis of any peculiar reflection in the upper strata of the atmosphere is more clearly excluded by the following examples of similar phenomena seen in the east after sunset. Captain NOBLE describes one seen by him on the 28th of August, 1883, at 10" 35" P.M. "For a moment I thought I was tracing the apparition of a new and most glorious comet." It was seen in the east-northeast. His description appeared in Knowledge, and it seems that Mr. W. K. BRADGATE saw an appearance at Liverpool on the same night and in nearly the same direction that Captain NOBLE had seen it in Sussex, but the hour was so much later that it could hardly have been the same object. Then followed an account of a similar appearance seen by Mrs. HARBIN at

Yeovil at 8 30" P. M. on the 21st of September, 1883, also in the east-northeast.

I saw a similar object myself on the 4th of September, 1885. It was in the east or east-northeast, and it was near 11 o'clock P.M. when I saw it. I took it for a very fine meteor-train, and described it as such in a letter to The Observatory. But I saw no meteor, and a comparison with the descriptions of Captain NOBLE, Mr. BRADGATE, and Mrs. HARBIN in Knowledge led me to conclude that what I had seen was of the same kind. As far as these scanty data go, these appearances seem to occur in spring and autumn, being in the west in spring and in the east in autumn. The resemblance to the tail of a comet presented by them has struck many observers, and I am inclined to think that on certain occasions they have been mistaken for comets' tails.

The first of these which I shall notice occurs in The Annual Register for 1761:

"July 18. At a quarter past eleven o'clock at night, a comet was seen off the quarter of His Majesty's ship Princess Royal at the Nore during nearly half a minute, very bright and light, but the clouds being thick obscured it presently. It had a very long tail and appeared to the E. S. E."

A real comet of this magnitude could not have escaped other observers. Clouds, however, seem rather a frequent accompaniment of the kind of phenomenon with which I am dealing.

On the 9th of April, 1894, Mr. EDWIN HOLMES announced that he had discovered a bright comet in the constellation Draco. Mr. HOLMES had discovered a comet not very long before, and the resemblance must have been striking in order to deceive him. Unfortunately, I have not the details of his observation at hand, but I have doubt that he mistook one of the appearances on which I have been commenting for a comet. The same remark applies to the discovery of a comet, or rather comet's tail, by Mr. EDDIE at Grahamstown, in South Africa, some time previously, but I do not recollect even the date of this announcement. The failures of astronomers are apt to be speedily forgotten. But clearly they saw something; and I believe both. Mr. HOLMES and Mr. EDDIE saw it with the naked eye. That it was not the zodiacal light, or a meteor-train I am convinced; nor do I think that these appearances are explicable as auroras, though that solution seems, on the whole, more probable.

I have not hitherto seen any notice of this phenomenon on the