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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 sin all 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 Innar 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 nebulæ, 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 liave such a direct connection with navigation and sea. longitude, 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 maile 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 are, emphatically, evangelical; not Truth. By the Rev. Daniel Mac- merely treating of abstract truths, afee. Crown 8v0., pp. 520. London: however glorious in their nature, Published for the Author at the but setting forth the way of salvaWesleyan Conference Office. 1872. tion, and labouring to apply the
— These sermons are comprehen- Word to the hearer's conscience. sive; they embrace a wide area of The task of the reviewer is, to some sacred truth; they are also argumen. slight extent, anticipated by a distative, not simply stating, but de. criminating and suggestive preface fending with acknowledged ability, from the pen of the Rev. William " the things which are most surely Arthur, A.M. Indeed, the venerable believed among us.” And they author may well be congratulated on his good fortune in having an knowledge when he saw Abraham editor so painstaking as Mr. Bush, afar off, and Lazarus in his bosom. and such a friend as the writer of Eternity is the region of necessity. the preface to introduce his volume Sinners of every class, who have to an expectant public, many of died in unbelief, necessarily know them already warmly prepossessed now what they were once called in the preacher's favour. We doubt upon to believe. Faith, not knownot that those who heard Mr. ledge, is the condition of salvation. Macafee in former years will be The testimony which faith lays truly glad to have in a permanent hold of belongs only to this state form sermons which must have of probation; and, consequently, yielded them both pleasure and when it is no longer borne, deprofit. And the younger preachers parted unbelievers cannot possibly of Methodism will do well to ac- fulfil the condition, and, hence, are quaint themselves with so interest- lost for ever."-Such weighty words ing a specimen of the way in which of warning as the foregoing deserve some of the fathers in our Israel solemn consideration in these days have been accustomed to set forth of insidious error. the Word of Truth. The volume will surely attain, as well as deserve, Physiology of the Soul and an extensive circulation. In illus- Instinct, as distinguished from tration of Mr. Macafee's style, we Materialism. With supplementary shall give one paragraph from his Demonstrations of the Divine somewhat celebrated sermon on Communication of the Narratives the blood of the Paschal Lamb. of Creation and the Flood. By
“ The sprinkling of the blood of Martyn Paine, A.M., M.D., LL.D. Christ must be done in the day. New York : Harper and Brothers. time. It is in the day of life, and 1872.- The separate existence of before the night of death cometh, mind, both Divine and human, is one that we must seek a conscience of those questions which necessarily sprinkled with His blood. *This occupy much attention in a sceptical is the work of God, that
Those who desire to dispense on Christ, whom He hath sent.' with the idea of a personal God are This can be done only in the pre- equally disposed to reduce the soul sent life. See how the case stands of man to a mere expression of The Scriptures teach that, from physical development. Men are beginning to end, salvation is by inclined, according to their mental faith. • He that believeth and is structure, either to transcendental. baptized shall be saved ; but he ism or empiricism. In the one that believeth not shall be damned.'
case, the sceptic arrives at Panthe. Can a man believe after he has left ism; and in the other at Positivism, this world ? He cannot; because The one proclaims a nature-god; he goes into a region where testi. and the other a law-god. There is mony is unnecessary, and cannot practically little or no distinction possibly subsist. Faith, however, between them. Pantheism is but is the child and associate of testi- an attempt to escape from the mony, and cannot be exercised assertion of Atheism ; and governwhen testimony is done away; and ment by physical law is unmitigated no faith, no salvation. The faith of Materialism. The existence of the the rich man was changed into human soul, as a self-acting being,
is involved in the question of the soul's superiority to and separate Divine existence. In asserting its existence from matter are inferred. existence and immortality, Dr. “The Creation and Organization of Paine enters the lists against all the Earth," the “Flood," and "The opponents. He proposes to con- Coal Formations” are treated in fine his proofs to arguments drawn appendixes, for the purpose of more from physiology. It is a bold fully elucidating the portions of position to assume ; but our author the argument in which reference is brings to his task the knowledge of made to these subjects. a master in physiological science, Dr. Paine's success in the line the skill of a metaphysician, and which he has taken is scarcely com. the results of extensive reading. plete. The existence of the immaThe literature of his complex sub. terial and immortal part of man ject seems to have been exhausted may be best demonstrated from its by him. Certain physical results direct manifestation and action. are held to be obviously produced This is, however, by no means an by different causes, traceable in ordinary book. It is a very their different modes of operation, armory for weapons against Ma-the one physical, and the other terialism. But we fear the form mental,-showing the independent in which its contents are presented existence of the soul. This is fur- will largely militate against its usether proved from the doctrine of fulness. The volume extends over final causes, illustrated by the re- seven hundred octavo pages, and lations of the various parts of the embraces topics which could have living organism to each other, thus been much more successfully treated evidencing a perfection of design in separate volumes. It is a book beyond what appears in the mere for students. structure of the animal form. The Divine existence, and creative wis- The Dangerous Classes of New dom and purposes are apparent: York. By Charles Loring Brace. and so the fact of the soul's sepa New York : Wynkoop and Halrate existence appears in the ability lenbeck, 1872. 8vo., pp. 448.— of man to read the evidences of the This work claims attention by its Divine existence.
mournfully graphic descriptions, An elaborate argument is con- valuable statistics, suggestive ducted to demonstrate the absurdity counsels, and earnest appeals. Its of Materialism in all the forms in object is to prove that the cheapest which it is advocated. The Mosaic and most efficacious way of dealing narrative of the Creation is largely with “the dangerous classes” (a discussed, and made to contribute term at which we will not stay to its portion to the general argument. cavil, for though not used in this It will be thought, however, by country, it is sufficiently undermany orthodox theologians that stood) is not to punish them, but here Dr. Paine aims at proving too to prevent their growth; to surmuch, and renders the harmony round them with the advantages of revelation and science impossible. of education and discipline and Considerable space is devoted to religion, and so to draw them under the relation between instinct and the influence of “the moral and reason, in which the distinction is fortunate classes,” that they may shown in manifold forms; and the become profitable members of the