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Europe, (meaning, we presume, modern literature, and attributes it principally to the circumstance of so large a share of it having fallen into the hands of the clergy, he certainly does not speak without reason : but he adduces one only out of many
and diversified causes. The general moral feelings of the readers should be estimated, as well as the sense of propriety in the writers; and it is not sufficient to say that the former have been gradually superinduced by the latter. Partially they may have been, but literary history shews us that authors have followed the prevailing taste of their times nearly as often as they have directed it.
ART. IX. A Practical Treatise on finding the Latitude and Lon
gitude at Sea: with Tables designed to facilitate the Calculations. Translated from the French of M. De Rossel, late Captain in the Navy,' &c. By Thomas Myers, A.M. of the Royal Military Academy, Woolwich, &c. 8vo. 165. Boards.
Robinsons, &c. . It may undoubtedly be said that in no country
in the world is a correct knowlege of navigation so highly important as in our own, on account of the magnitude of our navy, the extent of our commerce, and the number of our foreign possessions : nor can any state boast of better practical navigators, or more skilful pilots: yet, if we are rightly informed, they do not stand equally pre-eminent with regard to their scientific acquirements. This deficiency is probably owing to an unusual paucity of elementary treatises on nautical science. Hamilton Moore is the oracle of our midshipmén; and, in their opinion, whatever is there is right, and whatever is not there is at least unnecessary: so that it is nearly as likely to find a midshipman's locker without a Hamilton Moore, as it would be to see a farm-house unprovided with “ The Pilgrim's Progress,” and “ The Whole Duty of Man.” Few persons, indeed, are properly qualified to compose an elementary treatise on nautical astronomy; to accomplish which, in such a manner as will be creditable to the author and useful to the student, it is necessary that the former should possess a good practical and a good scientific knowlege of the subject; an union of qualifications not very frequently found in the same person. An instance, however, occurs in the author of the present treatise; who, besides much practical skill, acquired in his professional duties as a captain in the French navy, bears also a high scientific character, being well known as the friend and associate of the celebrated Ď Entrecasteaux. It is, perhaps, but justice to M.
Rossel to add here, from the translator's preface, the opinion of M. Biot, in whose Astronomie Physique this treatise was first published, and who thus describes the nature of the work and the qualifications of its author :
"" There is one branch of astronomy which has never been treated in a convenient manner in elementary works, because this required great accuracy and simplicity joined to an experience beyond what most men have an opportunity of acquiring. This is Nautical Astronomy; which has either been treated too superficially or in much too scientific a manner for mariners. I have, however, been very fortunate in having this part added to my work, by one who ranks among those who are best qualified to write on the subject. This is M. de Rossel, late Captain in the French Navy, coadjutor in and writer of the voyage of D'Entrecasteaux. The observations made by M. de Rossel and the other officers, during the voyage, have generally been regarded as the most accurate ever made in
French maritime expedition; and M. de Rossel's discussion of them as constituting an excellent treatise on Nautical Astronomy. It is a treatise of this kind, but more simple and concise, which this author has added to my work. It will be found to contain all the methods of calculation requisite at sea, and, what is not less valuable, they are given under the most simple and commodious forms that can be .employed in their application. Mariners will not fail to remark the ingenious tables which M. de Rossel has calculated for facilitating the use of Douwe's method of finding the latitude from two observations of the sun taken out of the meridian. This method, which may frequently be of great utility, is rendered so easy and convenient, by these tables, that its use will doubtless become fa. miliar to all mariners."
Such a recommendation of this treatise, from a mathematician so qualified to appreciate its merits as M. Biot, seems to have induced Mr. Myers to translate it into English ; and, in order to render it the more complete, and better adapted to perfect the young mariner in the most difficult branches of his art, he has added a considerable number of practical examples; an Introduction to the Tables, explanatory of their Construction and Use; a Table of the Right Ascensions and Declinations of the principal fixed Stars, used in finding the Longitude at Sea; a Table of the Logarithms of Numbers, and their Complements, to five Places of Figures; and a Table of Logarithmic Sines and Cosines, with their Complements, and Differences corresponding to every 10 Seconds. To all these we are glad to find that he has likewise subjoined Dr. Brinkley's method of clearing the lunar distance; a method which we strongly recommended to nautical students, and writers on navigation, in our review of the Transactions of the Irish Academy, vol. xi. (see M. R. vol, lxxiv.) The mcrits
of this rule consist in its involving no distinction of cases, ree quiring only short tables with single arguments; and no proportional parts being necessary, except such as may be taken out by inspection, and these for only one quantity besides the conclusion. The tables to which we here allude are given by the translator : so that the work contains in itself all that is requisite for the complete solution of every useful case in nautical astronomy; the mariner being of course supposed to possess the proper Nautical Almanac. The problems which the translator has added as practical examples for the student are principally adapted to the Almanacs of the years 1814 and 1815; which, therefore, will also be requisite while the student is merely pursuing his investigations.
The original work is divided into seven chapters, with notes, and an appendix : viz. 1. Preliminary Observations, &c. 2. Corrections which should be made in all the observed Altitudes of the Sun, Moon, and Stars.
oon, and Stars. 3. On Latitude, and the several Methods of Calculation. 4. Caleulation of the horary Angle, and of the Altitudes of the heavenly Bodies. 5. On regulating marine Chronometers, and employing them in the Determination of the Longitude. 6. On finding the
Longitude by Means of the lunar Distance. 7. On finding the Declination of the magnetic Needle by Observations of the Sun's Azimuth, or Amplitude, and by the astronomical Bearings of terrestrial Objects. The notes which follow contain the analytical investigations of the preceding rules; and the appendix is occupied with the solutions, at length, of various problems, while others are left as practical exercises for the student, with their
Next follows Dr. Brinkley's method of clearing the lunar distance; which, in order to assist in giving to it all the circulation that its simplicity renders desirable, we shall transcribe :
1. Find, by help of a table, the parallax answering to the moon's altitude, and to the complement of the altitude. The latter will be the argument of table 1. Or
Compute them by adding the proportional log. of the horizontal parallax to the arithmetical complement of the log. cos. and log. sin. of alt., the sums will be the prop. logs. of the respective parallaxes.
2. Moon's par. moon's refrac. = corr. of alt. Take diff. of (corr. of altitude + star's or sun's refraction + moon's alt.) and star's altitude (or sun's alt. + par.) This diff. is the diff. of true altitudes. Find also diff. of apparent altitudes.
3. When the sun is observed, add together the numbers in tables 1, 2, 4, and 5. When a star is observed, add the numbers in tables 1, 2, 3, and 5, log. of this sum (its index being always 3 + number of figures), + log. (vers. sin. observed distance
vers. sin. diff. observed altitudes) rejecting 10 from the index log. of a number to be subtracted from the above diff. of versed sines.
• 4. The remainder + vers. sin. diff. of true altitudes = vers. sin. of true distance.
• Observation. No distinction of cases occurs. No proportional parts but such as are taken out by inspection. The versed sines may be considered as whole numbers, the radius being (1,000,000). In taking out the versed sines of the observed distance, the seconds may be reserved and added to the conclusion. Also in finding the log. of (vers. sin. observed distance vers. sin. diff. obs. alt.) the two last figures may be considered as cyphers.
For those conversant in contracted decimal multiplication, the third precept may stand as follows:
3. When the sun is observed, take the sum of the numbers in table 1, 2, 4, and 5. When a star, the sum of the numbers in table 1, 2, 3, and 5. Find also the excess of the versed sine of the observed distance, above the versed sine of the difference of ob. served altitudes. The figures in the above-mentioned sum must be increased to five, if necessary, by prefixing cyphers to the left hand of them. Place the first figure of the sum under the third figure of the excess from the right hand, the second figure under the fourth figure of the excess, &c., thus inverting the figures of the sum. The product found, according to the method of contracted decimal multiplication, is to be subtracted from the excess.'
Mr. Myers's introduction to the tables, occupying about 20 pages, succeeds to the above; and lastly we have the tables themselves, which are eighteen in number, and are contained in 114 pages.
The whole of this volume, both text and tables, with the exception of two or three of the latter, which seem to be the work of another hand, is very neatly printed ; and, as far as we have been able to compare the translation with the original, we think that Mr. Myers has done jastice to his author: so that, considering also the additional examples and the several notes and illustrations, he has performed an useful service to the British mariner, to whom we recommend an attentive perusal and study of the work.
Art. X. The History of the University of Edinburgh; chiefly
compiled from original Papers and Records never before published. By Alexander Bower, Author of the Life of Luther.
2 Vols. 8vo. Il. 4s. Boards. Murray. 1817. OPPORTUNITIES for acquiring every
branch of knowlege are now so generally afforded, and brought so much within the reach of all descriptions of persons, - we meet on every side with so many solicitations of teachers, and so many notices of treatises all professing to convey information with the smallest portion of exertion to the pupils, - that we are apt to think that this facility and amplitude of instruction have always existed, and that they are regular and necessary concomitants of a state of society civilized in any ordinary degree. The slightest recurrence, however, to the history of the progress of the human mind, from the time of its torpor and depression under the great political calamities which so long overwhelmed the most civilized nations of Europe, is sufficient to convince us that opportunities of acquiring even the rudiments of learning were at one time unknown, or extremely scanty; and that those which we estimate now as very small and common attainments were once considered as high intellectual acquirements. In the course of such inquiries, too, however rapid, we cannot fail to regard with veneration those men who, by their mental energies alone, and unassisted by any of those advantages which so essentially aid the progress of the modern student, vanquished the difficulties of their situation; and who, diffusing in their life-time a spirit of literary improvement over a widely extended circle, left, at their death, a record of laborious exertions to which the men of the present day are rarely equal.
It appears to us, therefore, that the history of distinguished seminaries, from their first rise, must always be interesting; - not only as shewing the progress of human attainments, but as also exhibiting certain important aspects of the collateral history of civil society, and the mutual action of each on the other.
The University, of which the history forms the object of the work before us, has long held a distinguished rank among seminaries of learning. Men of great reputation in all the various branches of human knowlege have successively occupied its chairs; and the pupils who have been subjected to its discipline have filled with the highest celebrity many of those departments in civil life, which afford the greatest scope for the display of talent and enterprise. Yet the University of Edinburgh is the youngest of all the seminaries so denominated in Great Britain. It was not founded till after the Reformation; and it had consequently, from the first, comparatively few of the peculiarities arising from the monastic institutions which, even at this day, form a distinguishing characteristic in the constitution and rules of all the other establishments of this nature. It also differs from all the rest with respect to its endowments; which are so scanty that the emoluments of the professors depend chiefly on the fees which