The altitudes Nos. 231-239 were computed from the observations. A part of those from No. 25 to No. 87, are taken from Feldt's article, Astr. Nach., xvi, 339. A few numbers in the sixth column represent the height of the middle point of the path, as Nos. 281-284.

The altitudes Nos. 313-340 are taken from a diagram given by Herschel in the Proceedings of the British Meteorological Society. I have not seen the printed results of Prof. Heis's observations. But as the series is very much more reliable than most of those in the table, I have ventured to add it to the rest, although the numbers are liable to considerable error in the two processes, of engraving, and of measuring from the diagram.

2. On Sun-Spots and their Connexion with Planetary Configurations; by BALFOUR STEWART, Esq., Observatory, Kew. (Proceedings of Royal Society.) The author was led to investigate the solar autographs taken at Kew and Cranford, under the superintendence of Mr. Warren De La Rue, with the view of ascertaining if the behavior of sun-spots has any reference to planetary configuration. The following law was found to hold:-If the sun's disc be full of spots at any time, and if one of these begins to wane as it comes up by means of the sun's rotation to a

certain elliptical longitude, another will do the same. In fine, all spots at the same time behave in the same manner as they pass the same longitude. The author then remarked that, although this mode of investigation can only be considered as approximate, yet it furnishes us with an extremely delicate test of the fact of planetary action; for, if it be once clearly proved that sun-spots behave in this way, the only possible explanation is an influence from without. It was then shown that the influence of the planet Venus appears in this respect to be particularly pow erful, the law being that, as any portion of the sun's disc recedes from the neighborhood of Venus, it acquires a tendency to break out into spots, while, as it approaches Venus, these spots begin to heal up. The author then referred to Mr. Carrington's observations on sun-spots, which appeared to indicate that the period when Jupiter is farthest from the sun is most favorable for the development of spots over all portions of the sun's disc, more or less (the sun's diameter being here small compared to the distance of the planet). Coupling this with the observation regarding Venus, it may perhaps be inferred that the approach of a planet to its primary is favorable to luminosity, while the secession of the planet is favorable to spot production. Proceeding now to variable stars, the best formal explanation of the phenomena there presented is given by that hypothesis which supposes the star to be partly dark and partly bright, and to rotate on its axis, presenting to us the dark and bright portions alternately; but this is physically improbable. If, however, we suppose a large planet to revolve near the star, we shall have, if the above law holds true, a bright part next the planet and a dark part farthest from it; and this appearance will revolve with the planet, and will be phenomenally equivalent to a body partly dark and partly bright. Again, if a large planet have a very elliptical orbit, there will be a long space of time during which the former is far removed from its primary, and a short space during which it is very near; and, if we assume the law stated above, we should here have a long time of comparative darkness and a short time of intense brightness. Such an alternative is presented to us by temporary stars. On the whole, therefore, this law seems to explain all that is yet known on this subject, and may, perhaps, be of use as a temporary hypothesis.-Reader, April 23, 1864.

3. Observations on the Spots on the Sun from Nov. 9, 1853, to March 24, 1861, made at Redhill; by R. C. CARRINGTON, F.R.S. With 166 plates. London: Williams & Norgate.-The following is from a notice of this great work (signed J. N. L.) in the Reader of May 7:-[A copy of the work has not yet reached us.-Eps.]

All our text-books tell us that the Sun turns on its axis, the period of his axial rotation having been deduced from observations of his spots. But, from the time of Galileo, who made the period of rotation about a lunar month, down to our own, authorities have differed very considerably. Thus Grant, in his "History of Physical Astronomy," gives a period of 27d 8b (he quotes no authority). Laugier found 25.34d, and later observers have made it still less.

Mr. Carrington now comes to the rescue, and tells us that the spots travel at different rates, depending upon their distance from the equator either north or south, and that the different rates are bound together by a law, so