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before us contains the most valuable information of this local nature, arranged under the Eleven Statistical Divisions of England. Very considerately it has been decided that each Division—which also includes Tables of the Ages of the People, of their condition as regards Marriage, and of their Birth places-shall be sold separately. Thus every District will be readily and cheaply supplied with official materials upon which the proceedings of all Local Administration may be to some extent grounded. Upon the value of such a collection of facts to the historian and the topographer we need not enlarge. Every Census makes a vast addition to our accurate knowledge of the Condition of the People; and without this knowledge the Annals of our country show only the outward workings of the political machine. The inner life of a Nation is to be traced in documents such as these—founded upon a perfect organization of the means of inquiry, and digested with an accuracy beyond all praise.

CHARLES KNIGHT.

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II.-RECENT OBSERVATIONS AND RESEARCHES ON

THE PHYSICAL CONSTITUTION OF THE SUN. From the time—now something more than a century ago—at which the foundations of Modern Astronomy laid by the genius of Newton, having become fully appreciated by mathematicians as well as by the votaries and teachers of the science, were admitted to their due place in the culture of the human mind, glorious accessions of knowledge have been made, equally adapted to the expansion of the mental powers of Man and to acquaint him with the place in Creation which has been vouchsafed him; to the nurture and refinement of his bodily faculties, and the supply of those wants which, in that advance ment" and amelioration of the mind we term civilization, are changing in their nature and extending in their objects. These accessions of knowledge are of two classes. One relates to the microcosm Man himself, his mental endowments, the structure and functions of his body, and the innumerable subjects of Organic Nature around him. The other class embraces those departments of science which inform us of the distribution throughout the Visible Universe of assemblages of matter similar to the World on which we live, and of the laws which govern that distribution and the motions by which in fact their stability is maintained ; together with the investigation of the properties of those particular forms of matter which, as constituents of our own Planet, are more immediately subject to our observation. Among the objects of inquiry belonging to these branches of the knowledge of nature, pre-eminence may be admitted to belong to the great Source of Light and Heat—the re-creative principles of all that we behold—which is the immediate origin of absolutely all the activities we see and enjoy on the surface of the Earth, and of those we must attribute to the other bodies of our Solar System, excepting only the activities of Human and Organic Life. And inseparably united with the Sun, as objects of that rational investigation on which in the largest sense we confer the appellation of “Natural Philosophy," are the Stars—the Fixed Stars of a former condition of science-which we conclude by an instinctive perception recognizing an irresistible analogy, to be the Suns of innumerable distant Planetary Systems replenished with life like our own ;-a conclusion which the onward progress of natural knowledge from day to day uniformly confirms without the intervention of a single step in retrogression.

The pre-eminence of Solar Astronomy and Physics—and perhaps Solar Chemistry also, as indicated by recent wonderful combinations of distinct methods of research-among the sciences relating, not to life itself, but to the ultimate bases by and through which it is exerted, and on which it may be said to rest, in their application to the paramount objects of all knowledge, the culture, expansion, and elevation of the Human Mind, is equalled only by that which belongs to it in their application to the arts of Human Life. The means of every kind by which are constructed and worked the great implements of industry and communication, the Ship, the Steam-engine, the Railway, and the Electric Telegraph, and those employed in obtaining from the crust of the Earth, transporting over it, and fashioning for use those peculiar forms of matter, the two metals, which by their characteristic properties—the combined strength and amenability to heat of the one, and the beauty and indestructibility of the other-mediately govern human affairs among the dominant races of mankind, all originate in the action of the Sun upon the Earth and the transmission of its activities to distant points of space.

Some of these accessions of knowledge in relation to the Sun itself, it is proposed in this article to submit to the reader's attention, and especially to present him

with those derived from the progress of inquiry into its Physical Constitution, which have been made during the period measured by the last few revolutions of the Earth around it, from about 1859 to 1863.

To enable the reader to bear in mind the scale on which the Solar activities are carried on, and so to appreciate the grandeur and real import of the operations we shall have to describe, it will be useful here to introduce a few facts relative to the Sun which are expressed by numbers.

The mean distance of the Sun from the Earth, as recently estimated, is 91,328,600 miles; or about 384—not much less than 400 -times that of the Moon.

The diameter of the Sun is 850,100 miles; or more than 107 times the mean diameter of the Earth. A mountain upon the surface of the sun, to bear the same proportion to its diameter that the highest peaks of the Himalaya do to the diameter of the Earth would require to be above 600 miles in altitude.

The circumference of the sun is 2,671,000 miles. * • The distance of the Sun from the Earth and the diameter of the former, have been taken from Mr. Hind's statement of them as corrected from M. Le Verrier's estimate of the solar parallax, and published by him in the · Times' newspaper for Sept. 17, 1863; that estimate being one ground of the recent determination by astronomers that we are nearer the sun by about 4,000,000 miles than for many years past has been commonly believed. The volume and mass of the sun which follow have been left as given by Mr. Hind in his Introduction to Astronomy, their correction being unimportant for the mere purpose of comparison we have here in view,

The volume, solid contents, geometrically speaking, or bulk of the Sun exceeds that of the Earth 1,405,000 times : in other words, it would take that number of Earths to make one globe of the same magnitude as the Sun. This is 600 times greater than the bulk of all the planets at présent known to exist.

The mass of the sun, or the quantity of matter it contains as measured by weight, and known by its attractive power, exceeds that of the Earth 356,000 times, and is 740 times greater than the masses of all the known planets put together.

The period of the rotation of the sun upon its axis, which takes place in the same direction as that of the Earth, or from west to east, is about 25 days 8 hours ; the excess over the 25 days is uncertain in exact amount, but actually exists. It is probable that the distinct spherical strata or shells of which the sun consists differ slightly in their periods of rotation, whence, in part, the uncertainty seems to arise.

The north end of the axis, or North Pole of the Sun leans seven and a half degrees from a perpendicular to the Earth's path.

The diameter of the sun is nearly four times greater than that of the Moon's orbit around the Earth, which is 238,000 miles, or nearly 30 times the diameter of the Earth; so that if the Earth were placed in the centre of the Sun, the moon would revolve at a depth within the sun of more than 187,000 miles from its surface.

Perhaps another kind of familiar illustration may be useful. Nothing which assists the mind to comprehend so wonderful a subject as that before us can rightly be considered undignified. A Railway Train at the average speed of thirty miles in an hour, continuously maintained, would arrive at the Moon in eleven months, but would not reach the Sun in less than about 352 years, so that, if such a train had been started in the year 1512, the third year of the reign of King Henry the Eighth, it would reach the Sun in 1864. When arrived, it would be rather more than a year and a half in reaching the sun's centre, three years and a quarter in passing supposing it was tunnelled through, and ten years and one-eighth in going round it. How great these dimensions are may be conceived from the statement that the same train would attain the centre of the Earth in five days and a half, pass through it in eleven days, and go round it in thirty-seven days.

The first subject of recent investigation we have to notice is that of the Form or Figure of this luminary.

The polar and equatorial diameters of the sun's disc as observed, have been supposed to differ, though by a very small quantity only, and either has been believed to exceed the other. The observations of Maskelyne and Littrow make the figure of the sun that of a prolate spheroid, having the polar diameter greater than the equatorial ; while those of Carlini and Bianchi make it an oblate spheroid, like that of the earth, the polar diameter being less than the equatorial. Observations of equal excellence and calculations of equal accuracy, instituted by equally competent astronomers, having these opposed but complementary results, it would seem a rational and satisfactory conclusion that the form of the disc is a true circle; and since we

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observe the sun in a direction nearly at right angles with its axis, and nearly coinciding with the plane of its equator, it would seem equally satisfactory to conclude that it must be a solid of revolution, and the visible disc being sensibly a perfect circle, that the figure of the sun must be sensibly a perfect sphere. But doubts as to the true figure of the sun having been lately raised, they have been met by reference to the measures of Schlüter and Wichmann, which, according to Dr. Winnecke, “determine the question for the present position of the science of observation,” giving perfect equality of the diameters. Still, however, “it has been proposed lately to prepare an apparatus for the purpose of examining whether the sun's disc is really circular, and, in particular, for ascertaining whether the diameters nearly perpendicular to the ecliptic are equal to those nearly parallel to the ecliptic.” The Astronomer-Royal, however, has finally shown, that no new information could be given by such apparatus regarding the measures of the sun's diameters, in any degree comparable to that which we already possess in the Greenwich Observations, made from the year 1836 to the present time ; and the evidence afforded by which is growing every day, giving at present a horizontal diameter exceeding the vertical only by 0". 1; that is, by the 1930th part of the entire angular or apparent diameter of the sun. This, it will be easily believed, Mr. Airy is correct in saying is a

quantity smaller than we can answer for in these or in any other methods of observation.” Therefore, again, we have a right to say that the disc is a perfect circle, and to conclude the truth to be that the sun is a perfect sphere; being indeed the only body of the solar system having that figure, and the only known example of a perfect sphere in nature, though it would seem possible that the stars —the distant suns of other systems—may agree with our sun in this respect.

The phenomena of the perspective projection of the sun on the visual plane-on the retina of the eye, in fact-called his disc,-the visible sun,--and the perfection of his figure, are reciprocally connected; we infer the latter from observations on the former, and we find the exact circularity of the disc again to be the consequence of the perfect sphericity of his figure. But not only is the disc geometrically perfect in the equality of its diameters, it is bounded also by a mathematically perfect curved line : though we know that there are great inequalities in the surface of the sun, the contour of his disc is continuous and unbroken. The “ Luminous Prominences” total eclipses of the sun, when the solar illumination of our atmosphere is locally nearly extinguished by the intervention of the moon, and which have attracted so much attention of late years, do not impair the uniformity of this outline, but are apparently based upon or exist beyond it. Preparatory, however, to inquiring into the cause of this simplicity and exactness of visible contour, we must briefly review the phenomena presented for observation within or upon the disc, from which all our notions of the physical constitution of the sun are obtained ; and especially those which have been recently discovered or investigated. • The mottled or curdled appearance which astronomers who have

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viewed the sun through powerful telescopes have described as characterising its entire surface—the surface, that is, of the photosphere, or outer luminous envelope of the sun, and the brighter portions of which have been termed faculce—is described by Mr. Warren De la Rue, from his large photographs, as arising from the fact that the visible photosphere is entirely composed of an undulating mass of waves like the surface of the sea agitated by wind; a description which is in harmony both with the accounts and the inferences of other observers. But according to the observations of Mr. James Nasmyth, communicated to the British Association in 1862, the entire luminous surface consists of an aggregation of greatly elongated, lenticular-shaped masses, resembling in figure Willow-leaves, and some forms of Diatomaceæ, interlacing with and superposed on one another in every possible direction. They are said by Mr. Nasmyth to be “ arranged without any approach to symmetrical order in the details, but rather (if the term may be used) in a sort of regular random scattering." He found them also to be in constant motion relatively to one another, sometimes approaching, sometimes receding; and sometimes assuming a new angular position with respect to each other, by one end of a lenticular mass either maintaining a fixed distance from, or approaching one end of its neighbour, while at the other ends they retired from each other. They were observed to shoot in comparatively narrow streams across the enormous chasms we call the spots of the sun,“ bridging" them over in well-defined bands or lines, and appearing to adhere to one another by lateral attraction. The appearance resulting from the combination of simultaneous motions which they present, is compared to that of a dense shoal of fish, which they also individually resemble in form. The spots also exhibit the extremities of these leaf-like bodies pointing inwards, and fringing the sides of the cavern far down into the abyss ; sometimes by crowding in on the edges they close it in, and frequently at length coliterate it. These bodies are stated to be of various dimensions, some being as large in superficial area as all Europe, and some even as the entire surface of the Earth. In general their length exceeds their breadth nine or ten times, at the middle or widest part; the former measuring not less than 1,000 miles, by a breadth of about 100 miles, while their height or thickness, doubtless very great, is as yet entirely unknown : the entire bulk of a “lenticular body," therefore, immensely exceeding that of the greatest group or range of mountains on the earth. All these dimensions may be regarded as proportionate to the grandeur of the scale on which solar phenomena are carried on; but the greater ones probably apply to lateral aggregations of the elementary lenticular objects.

Mr. - Dawes had previously found that the interior edge of the penumbra, or less dark border of the spots, frequently appears extremely jagged; the bright ridges on its surface, which are usually directed nearly towards the centre of the spot, being seen projected to irregular distances on to the cloudy stratum (a region of the spots between the penumbra and the dark nucleus, and first observed by Mr. Dawes, as will be noticed hereafter), "and looking much like a piece of coarse thatching with straw, the edge of which has been left

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