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few degrees for adjusting the line of collimation, and can be subdivided into seconds by means of a micrometer screw. The quadrant is first placed in a vertical position by means of the fpirit level or plumb line. The difference between the arc and 90', or the correction of collimation, may be found by inverting the inftrument, or more conveniently by means of the zenith sector or adjusting telescope. The limb confifts of two graduations; the inner into go equal parts, the outer into 96. Mr. Vince gives a particular detail of the use of the instruments, and introduces a rule of Dr. Maskelyne's for determining the latitude and longitude of a star from its right ascension and declination, which; for its neatness and simplicity, deserves a place here. 1. let log. fin. f. ascen. + log. cotang. decl. = log. cotang. A. 2. put arc. 'A + obl. eclip. = B. 3. arith. comp. cos, Ā + cos, B + tan. r. ascen. = tan. longitude. and 4. log. fin. long: +tang. B = tan. latitude.
In Chap. VI. Mr. Vince describes the ĉontrivances for meafuring the apparent diameters of the planets, and the angular distance of the objects which come into the field of view. The celebrated Huygens first placed, in the principal focus of the object-glass and perpendicular to the central wire, two plates, whose edges were parallel and well defined. To these were afterwards substituted two parallel wires. The micrometer, as it is at present constructed, consists of a system of parallel and equidistant wires; by which means the angular distance of the heavenly bodies, which pass successively through the field of view, can be determined, and thence their declination and right ascension. Mr. Savery suggested the idea of forming two images, which was adopted and improved by Mr. Dollond. The objectglass is divided into two segments, in a line drawn through the centre, and each is fixed to a separate moveable frame of brass. Hence the angular distance of two distant points will be found by separating the segments till the two images coincide ; and thus any diameter of an object, whatever be its inclination to the direction of the apparent motion, may be determined with equal ease and accuracy. This contrivance may also be applied to discover the difference of declinations and right ascensions, and also to ascertain the place of a planet on the sun's disc. But the object-glass micrometer, however valuable, is attended withi some inconveniencies, arising from the variation in the state of the eye of the observer. Dr. Maskelyne has been led to the discovery of a new contrivance, which is very ingenious. He does not alter the object-glass, but places two very acute glafs prisms between it and the principal focus. The divarication of the two images that are formed is evidently proportional to the distance of the prisms from the focus. The difficulty, was to
determine the beginning of the scale, because the angle vanilhed when the prisms were placed in the focus. Dr. Maskelyne af terwards divided the object-glass, and siding the segments a little, he separated the images, and, by means of the prisms, formed one distinct image, and thus fixed the commencement of the scale. Mr. Herschel has applied what he calls a lamp micrometer to Sir Isaac Newton's reflecting telescope.
In Chap. VII, Mr. Vince describes the equatorial sector, and explains its various adjustments. This instrument was first constructed by Mr. Graham, and afterwards improved by Dr. Maskelyne. Its axis is parallel to that of the earth, and the te.. lescope fixed to it admits of any degree of elevation; and hence it is admirably fitted for observing the declination and right ascenfion of the stars.
The zenith sector was first constructed by Dr. Hook to measure small angular distances from the zenith, with the view of discovering the parallax of the fixed stars; but though the tube." was thirty-six feet in length, it was found liable to an error of 30". Afterwards, Dr. Bradley made, upon nearly the same principles, an instrument only 12 long, but the error of which did not amount to half a second. With this he began in 1725 to observe y Draconis, and, after a course of twenty years observations, he made the wonderful discoveries of the nutạtion of the earth's axis, and the aberration of light.
In Chap. VIII, our author describes very particularly the equatorial telescope, constructed about the year 1749 by Mr. Short. The instrument is extremely complicated, susceptible of a variety of movements, and requires numerous adjustments. It is fitted for almost every purpose, and may be considered as a compendium of astronomical apparatus.
In Chap. IX, we have an account of the instrument fately invented by Mr. Ramsden for measuring horizontal angles. In the year 1785, in consequence of a memorial presented by the French ambassador, ftating the uncertainty of the longitudes of the observations of Paris and Greenwich, and the importance of ascertaining the difference with accuracy, his majesty ordered the measurement to Dover to be carried on and completed at his own expence, and under the direction of the Royal Society of London. General Roy was appointed to conduct the bufiness; and, upon this occasion, Mr. Ramsden constructed, on a new principle, an instrument of extreme accuracy. The Ge. neral, in an account of his operations read at the late meetings of the Society, has given a very minute detail. We shall therefore have a better opportunity afterwards of describing the inftrument. It was found that the difference of the meridians ENG. REV. VOL. XV. APRIL 1790.
of Paris and Greenwich was 9' 20", in time the same with what Dr. Maskelyne had before determined."
Chap. X. contains a particular description and an account of the adjustments of Mr. Ramsden's new circular instrument, which is much more complete than the mural quadrant, and not liable to the same defects. It can both measure azimuths and altitudes ; it is capable of a more accurate division; it is not subject to the errors of centre work, and it is not affected . by the change of position.
Mr. Vince next proceeds to give directions for observing,'' with the common telescope, the transits of Mercury and Venus over the sun's disc, the eclipses of Jupiter's satellites, and those of the sun and moon. He concludes with a short account of the doctrine of the interpolation of serieses, and illustrates, by examples, its application to astronomical observations. In a word, this treatise must be considered very complete, and highly useful to practical observers.
Art. III. A new English Translation of the Pentateuch; being a
thorough Correction of the present Translation wherever it deviates from the genuine Sense of the Hebrew Expressions, or where it renders obscure the Meaning of the Text; or, lastly, when it occasions a seeming Contradiction; proving the Validity of such Emendations by critical Remarks and Illustrations, grounded on other Infances in Scripture where the like Words or Phrases occur ; together with a Comment on such Passages as cannot be sufficiently understood by a mere Translation. Being a Work highly useful, and never before attempted. By Isaac Delgado, Teacher of the Hebrew Language. 4to. ios. boards. Richardson. London, 1789.
AFTER this copious title-page our readers will hardly re- ,
quire of us any account of the design of the work. In the preface the author, we conceive, means to explain to us what he means by a work never before attempted, viz. that in most of the family bibles the commentators, as Young complains,
• Each dark passage Thun,
And hold a farthing candle to the sun.' Mr. Delgado next gives his English reader a statement of some peculiarities in the Hebrew language, which are more than sufficient to account for the great variety of opinions in different writers. He likewise instances some modes of expression almost
confined to the sacred text, the want of attention to, or knowledge of which, has led many translators into feeming contra. dictions. After this he explains the plan he means to adopt in his own work, of consulting, wherever he finds himself deficient, the most eminent Hebrew expositors; and where he meets with nothing satisfactory in therm, he will leave the passage as unintelligible. But,' says our author,
'. I will never avail myself of that pernicious method of supposing an error in fcripture, committed by transcribers after the compilation of the Bible by Ezra and his fynod, who faithfully handed it down to us as they found it, without venturing to alter a single letter, and was fince preserved by the Masforites as pure as they received it, which will be proved by my observations on Joshua, chap. xxi. ver. 36. And it is worthy of notice, that all over the world, whereever there is a congregation of Jews, there is not any material difference in their Hebrew Bibles. But to pretend to correct the original Hebrew by the different reading's found in manuscripts lodged in private hands, which may have received many alterations by being copied from other manuscripts (in which some annotations, having been interlined, may have been introduced into the text), I think it prophane, as it would give us a spurious copy, instead of a divine narrative. However, I cannot deny that there are some apparent errors in scripture, but am firmly persuaded that they have been so ab origine, I mean before the compilation of the Bible by Ezra, and not committed since by transcribers : but this refers only to the rest of the Bible, exclusive of the Pentateuch, which was written by Moses ; therefore I cannot admit any error in it: besides, they are kept in the synagogues to be read weekly; and every copy is carefully ex. amined, that there be not a letter too much nor any missing in it; and, if an error is found at the time of its being read, it is laid afide, and another is taken out, and the first is given to a scribe to correct it; so that it seems to me almost impossible that there should be any error in it; whereas the other parts of the Bible, we do not know to a certainty who wrote them; for several of those books were certainly not written by those whose names they bear. And, not. withstanding that I aumit of some supposed errors in scripture ab origine, before Ezra, yet I am not clear that they were committed by inadvertency or mistake, thinking rather that they are purposely, introduced to give us some farther information than what the letter expresses, though we may not be able, at this distance of time, to penetrate what it may be.' We would willingly suppose scripture to have been originally written in such a manner as that every thing of sufficient importance to our duty was easily understood by all. We may say the fame of every passage of holy writ, even in these days. But, without supposing a constant superintendant miracle, we can hardly conceive, circumstanced as the Jews have been at different periods, that all their congregational copies are perfect. R2
Indeed it is well known they have not been all exactly similar. We cannot, therefore, help thinking that the world is under many obligations to the industrious Dr. Kennicot, who first had the courage to adopt the mode of giving us a correct copy of the Bible by comparing different readings. And we look with much impatience for the result of Dr. Geddes's labours in this most important branch of literature. We ought to observe too that Mr. Delgado refers his arguments on this subject to his notes on Joshua. Now the present performance, containing only the five books of Moses, we are left in the dark as to these arguments till his second volume appears. Till we see them produced we shall not be afraid to assert that, notwithstanding the confidence of Mr. Delgado's assertion relative to the Pentateuch, there is sufficient internal evidence to thew that though Ezra might be assisted by the Holy Spirit in his compilation, and though there is no reason to doubt the faithfulness of it, yet that in many parts he has not confined himself to the exact words of Mofes. To such as wish for a fair statement of this important question, we recommend a perusal of Dr. Prideaux's Connexion of the Old and New Testament. ...
, We need hardly observe to our readers that the paffage we have presented to them is liable to other objections. For want of a close grammatical construction, it is impossible to know whether Ezra and his fynod, or the subsequent transcribers, are supposed to be, thus faitẶful in handing down the scriptures s we can trace no nominative to the verb ' was preserved,' and the rest of the sentence is extremely confused. The author indeed makes an apology for the uncouthness of his language ; but this does not excuse incorrectness; and as Dr. Owen, among others, advised the publication, we fincerely wish he had lent his assistance in correcting the English. .
The work itself is undoubtedly entitled to no inconsiderable share of praise. To give our opinion of many of the emendations would be more than is expected of us, or than our limits would admit. Suffice it to say, the whole is evidently the work of much labour; and we recommend it as an useful addition to biblial knowledge. We have selected the following passages as specimens of the work, and because we think in them our au. thor's remarks will admit of a further commentary. The reader will observe, only so much of the old translation is given as the author has thought it neceflary to amend, or to make observations upon :