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Maskeleyne, and Pond. The tables of Mercury, Venus, aud Mars, are Le Verrier's, based chiefly upon the Greenwich observations from 1750 to 1830, which were, with the rest of the planetary observations for that period, reduced by Sir George Airy en masse, like the lunar observations. For the sun, Le Verrier's Tables are also used; and they depend upon a century's Greenwich observations. The current tables of Neptune are those by Professor Newcomb, for which Greenwich found the major part of the observational data. Throughout the whole series of Planetary Tables that belong to the period of accurate astronomy, there is such a broad reliance for data upon Greenwich, and such comparatively small support derived from other places, that it is evident there was no excessive flattery in Baron Zach's assertion that our astronomical tables would have been as perfect as they are if no other observatory had ever existed. All this we adduce, not with the idea of glorifying a national institution, but merely to aid the full conception of its mission, which was defined in Sir John Herschel's always happy words to be, "To furnish now and in all future time the best and most perfect data by which the laws of the lunar and planetary movements as developed by theory can be compared with observations."

It will be easily seen that with all things organized to this end, there is little room for such work as double-star measures, celestial photography, delineations of planets and nebula, spectroscopy, etc. Some of these have occasionally been taken up for a time, but none of them have been, or indeed could be, systematically followed.

Of late, however, there has been a tendency in some subjects of this character to overrun the powers of attention of amateurs to whom they have been left; and it has been suggested that inasmuch as they ought to be followed by the State, and Greenwich as at present constituted could not undertake the work, a special observatory ought to be established, and devoted to astronomical physics. The systematic record of solar phenomena (sun-spots, gaseous eruptions, etc.) has been mentioned as in immediate need of pursuit. Not unnaturally a counter question arose whether all that it was desirable for the State to undertake could not be done at Greenwich, and the astronomer-royal laid his views upon the general question before the Board of Visitors at their meeting in June last, in the following terms :—

The tendency of late discoveries and consequent discussions in astronomy has been, not to withdraw attention from the exact departments of astronomy, but to add greatly to the public interest in those which are less severely definite. And this has become so strong, that I think it may well be a subject of consideration by the Board of Visitors whether observations bearing upon some of those trains of discovery should not be included in the ordinary system of the Royal Observatory. The criteria which, as appears to me, may be properly adopted in the selection or rejection of subjects of observation are these: observations which can be made at any convenient times, which do not require telescopes of the largest size, and which do not imply constant expense, ought to be left to private observers; observations which demand larger telescopes, and especially observations which must be carried on in continual routine and with considerable expense, can only be maintained

at a public observatory. The claims of each subject must be separately considered; but there can be no doubt that a very powerful demand for attention is made when private persons have been induced to continue observations for a long time at considerable current expense, and when plausible evidence is given of the connection of results thus obtained with other cosmical elements. I think that these considerations exclude measures of double stars at the Royal Observatory, but they leave an opening for the scrutiny of nebulæ, planets, etc., and possibly (but I speak in doubt) of solar spectroscopy. But I have no doubt that they fully sanction the undertaking a continued series of observations of solar spots.

"The character of the Observatory would be somewhat changed by this innovation, but not, as I imagine, in a direction to which any objection can be made. It would become, pro tanto, a physical observatory; and possibly in time its operations might be extended still further in a physical direction."

Upon the effect of these statements it would be premature to speak. It is, however, generally understood that the Board decided upon the advisability of extending the Observatory system so far (for the present) as to include regular photographic records of solar spots and systematic solar spectroscopy. The Visitors are an intermediary body: before full effect can be given to their decision the Treasury must be appealed to for funds for the first cost of instruments and the running expense of an increased personal staff.

Chronometers have such a direct connection with navigation and sealongitude, that not unnaturally Greenwich has been identified with the testing of these instruments from their invention to the present day; and now it is the chief depôt for Government marine chronometers. All business of their purchase, trial, and repair, is transacted at the Observatory; and usually about two hundred chronometers are there under rating for issue to her Majesty's ships. Every year there is a competitive trial open to all makers, during which the chronometers are exposed to a wide range of temperature: four or six of the best instruments are each year purchased at good prices; and it is doubt. less to these trials and to the general Government patronage of the trade that the supreme excellence of British chronometers is due.

Into the department of time and its distribution we need not enter further than to say that a signal ball is dropped at one o'clock daily at the Observatory, and another ball at Deal is dropped by direct current from the Observatory; and that accurate electric signals go forth from Greenwich every hour, which are variously distributed over the country; one of them, that at ten A.M., passing through well-nigh all the important telegraph lines in England.*

A magnetical and meteorological department was established in 1840, and, till 1847, eye-observations of its instruments were made every two hours, day and night. In 1848 photographic registration was introduced, and from then till now there has been an unceasing record of the

A description of this interesting operation is given in this Magazine for 1871, pp. 325-330.

movements of the declination, horizontal force, and vertical force magnetometers, as well as of the barometer and the dry and wet bulb thermometers. The anemometers, for direction, force and velocity of the wind, and also a pluviometer, register themselves mechanically. The magnetic observations and registers to 1863 have been discussed, and the epitomised results form the subjects of various memoirs in recent volumes of the "Philosophical Transactions." It may be mentioned, that among other points these discussions negative the existence of a decennial magnetic period related to the period of solar spot activity. A great discussion of temperature records from 1848 to 1868 is now in progress. Within the past few years an important, and we believe unique, addition has been made to the photographic recording department. The spontaneous galvanic "earth-currents" that at times become so intense as to interfere with telegraphic operations, have been made to record themselves perpetually by reflecting galvanometers connected with special wires running in N.S. and E.W. directions through the Observatory, and attached to earth-plates at their extremities. A discussion of some of the registers has shown that these currents are related to the earth's magnetism in its disturbed state,-as during auroral displays, but apparently not in its tranquil state.

In conclusion, it should be stated that the Greenwich observations of all kinds are published in yearly quarto volumes of nearly one thousand pages each, in which every observation is set down in the utmost detail, with every instrumental reading as it is recorded by the observer, and (especially in the case of the astronomical observations) with every step in the reductions exhibited, down to the final results, which are given in such a form as to be directly available to the theoretical investigator.Popular Science Review.

SELECT LITERARY NOTICES.

[The insertion of the title of any publication in this list is not to be considered as pledging us to the approbation of its contents, unless it be accompanied by some express intimation of our favour. able opinion. Nor is the omission of any such intimation to be regarded as indicating a contrary opinion. Our limits, and other reasons, impose on us the necessity of selection and brevity.]

The Pillar and Ground of the Truth. By the Rev. Daniel Macafee. Crown 8vo., pp. 520. London: Published for the Author at the Wesleyan Conference Office. 1872. -These sermons are comprehensive; they embrace a wide area of sacred truth; they are also argumentative, not simply stating, but defending with acknowledged ability, "the things which are most surely Lelieved among us." And they

are, emphatically, evangelical; not merely treating of abstract truths, however glorious in their nature, but setting forth the way of salvation, and labouring to apply the Word to the hearer's conscience. The task of the reviewer is, to some slight extent, anticipated by a discriminating and suggestive preface from the pen of the Rev. William Arthur, A.M. Indeed, the venerable author may well be congratulated

on his good fortune in having an editor so painstaking as Mr. Bush, and such a friend as the writer of the preface to introduce his volume to an expectant public, many of them already warmly prepossessed in the preacher's favour. We doubt not that those who heard Mr. Macafee in former years will be truly glad to have in a permanent form sermons which must have yielded them both pleasure and profit. And the younger preachers of Methodism will do well to acquaint themselves with so interesting a specimen of the way in which some of the fathers in our Israel have been accustomed to set forth the Word of Truth. The volume will surely attain, as well as deserve, an extensive circulation. In illustration of Mr. Macafee's style, we shall give one paragraph from his somewhat celebrated sermon on the blood of the Paschal Lamb.

"The sprinkling of the blood of Christ must be done in the daytime. It is in the day of life, and before the night of death cometh, that we must seek a conscience sprinkled with His blood. This is the work of God, that ye believe on Christ, whom He hath sent.' This can be done only in the present life. See how the case stands. The Scriptures teach that, from beginning to end, salvation is by faith. 'He that believeth and is baptized shall be saved; but he that believeth not shall be damned.' Can a man believe after he has left this world? He cannot; because he goes into a region where testimony is unnecessary, and cannot possibly subsist. Faith, however, is the child and associate of testimony, and cannot be exercised when testimony is done away; and no faith, no salvation. The faith of the rich man was changed into

knowledge when he saw Abraham afar off, and Lazarus in his bosom. Eternity is the region of necessity. Sinners of every class, who have died in unbelief, necessarily know now what they were once called upon to believe. Faith, not knowledge, is the condition of salvation. The testimony which faith lays hold of belongs only to this state of probation; and, consequently, when it is no longer borne, departed unbelievers cannot possibly fulfil the condition, and, hence, are lost for ever."-Such weighty words of warning as the foregoing deserve solemn consideration in these days of insidious error.

Physiology of the Soul and Instinct, as distinguished from Materialism. With supplementary Demonstrations of the Divine Communication of the Narratives of Creation and the Flood. By Martyn Paine, A.M., M.D., LL.D. New York: Harper and Brothers. 1872.—The separate existence of mind, both Divine and human, is one of those questions which necessarily occupy much attention in a sceptical age. Those who desire to dispense with the idea of a personal God are equally disposed to reduce the soul of man to a mere expression of physical development. Men are inclined, according to their mental structure, either to transcendental. ism or empiricism. In the one case, the sceptic arrives at Pantheism; and in the other at Positivism. The one proclaims a nature-god; and the other a law-god. There is practically little or no distinction between them. Pantheism is but an attempt to escape from the assertion of Atheism; and government by physical law is unmitigated Materialism. The existence of the human soul, as a self-acting being,

is involved in the question of the Divine existence. In asserting its existence and immortality, Dr. Paine enters the lists against all opponents. He proposes to confine his proofs to arguments drawn from physiology. It is a bold position to assume; but our author brings to his task the knowledge of a master in physiological science, the skill of a metaphysician, and the results of extensive reading. The literature of his complex subject seems to have been exhausted by him. Certain physical results are held to be obviously produced by different causes, traceable in their different modes of operation, -the one physical, and the other mental, showing the independent existence of the soul. This is further proved from the doctrine of final causes, illustrated by the relations of the various parts of the living organism to each other, thus evidencing a perfection of design beyond what appears in the mere structure of the animal form. The Divine existence, and creative wisdom and purposes are apparent: and so the fact of the soul's separate existence appears in the ability of man to read the evidences of the Divine existence.

An elaborate argument is conducted to demonstrate the absurdity of Materialism in all the forms in which it is advocated. The Mosaic narrative of the Creation is largely discussed, and made to contribute its portion to the general argument. It will be thought, however, by many orthodox theologians that here Dr. Paine aims at proving too much, and renders the harmony of revelation and science impossible. Considerable space is devoted to the relation between instinct and reason, in which the distinction is shown in manifold forms; and the

soul's superiority to and separate existence from matter are inferred. "The Creation and Organization of the Earth," the "Flood," and "The Coal Formations" are treated in appendixes, for the purpose of more fully elucidating the portions of the argument in which reference is made to these subjects.

Dr. Paine's success in the line which he has taken is scarcely complete. The existence of the immaterial and immortal part of man may be best demonstrated from its direct manifestation and action. This is, however, by no means an ordinary book. It is a very armory for weapons against Materialism. But we fear the form in which its contents are presented will largely militate against its usefulness. The volume extends over seven hundred octavo pages, and embraces topics which could have been much more successfully treated in separate volumes. It is a book for students.

The Dangerous Classes of New York. By Charles Loring Brace. New York: Wynkoop and Hallenbeck, 1872. Svo., pp. 448.This work claims attention by its mournfully graphic descriptions, valuable statistics, suggestive counsels, and earnest appeals. Its object is to prove that the cheapest and most efficacious way of dealing with "the dangerous classes” (a term at which we will not stay to cavil, for though not used in this country, it is sufficiently understood) is not to punish them, but to prevent their growth; to surround them with the advantages of education and discipline and religion, and so to draw them under the influence of "the moral and fortunate classes," that they may become profitable members of the

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