this part of the work the Editor has made ample use of the Dir-
quisitiones Plinianæ of Count Rezzonico, a Venetian nobleman,
who published, not long ago, an excellent Italian translation of
Pliny. The whole will be concluded by three tables. The
firft will contain the names which Pliny has given to the dif-
ferent productions of nature, and, in a parallel column, the
names that are appropriated to the same productions in the fyr-
tem of Linnæus: and the second and third will exhibit a list
of the ancient authors which have been illustrated in the notes,
or quoted by Pliny.

M.

partly / and it /

MONTHLY CATALOGUE,

For MAY1778.
MATHEMATICS and PHILOSOPHY,
Art. 15. Mathematical Principles of Natural Philosophy. By Sir

Isaac Newton, Knight. Translated into English, and illuftrated
with a Commentary. By Robert Thorp, A.M. Vol. I. 46o.
il. I S. Cadell. 1777.

*HIS first volume of Mr. Thorp's translation of the Principia
T

comprehends the first book of that immortal work. The
commentary with which he has enriched this version, part of which of
is extracted from the works of Maclaurin, Saunderson, Keil, and
fome other writers,

is added with a view to supply those demonstrations which the Author had omitted, on the supposition that they were previously known ;-- to point out the extent and limits of problems; and to thew their practical use and application to the fyfo tem of the world.'

That the Reader may receive benefit from this commentary, the Editor requires only that he thould be perfectly well acquainted with the geometry of Euclid, the elementary parts of algebra, and a few of the primary properties of the conic sections. With a view to elucidate the use and tendency of the molt abitract propositions, several corollaries and philosophical scholia are added : and as the synıbetic form of demonftration is best suited to those for whose use the commentary is intended, Mr. Thorp has, in his notes, adopted the geometrical style of the Author. He has, however, occafionally made use of the Author's method of Auxions, which he has employed in a few analytical demonstrations of some

of the principal propotitions, B.y. Art. 16. The Elementary Parts of Dr. Smith's Complete System of

Oprics, selected and arranged for the Use of Students at the Unia
verfities. To which are added, in the Form of Notes, fome Ex.
planatory Propostions from other Authors, 410. 10 s. 6 d. fewed,
Nourse, &c. 1778.

The scarcity of Dr. Smith's Complete System of Optics having been
long a subje&t of complaint, particularly at the universities; and
there being no appearance of a speedy republication of the whole of
that excellent treatise: the prefent Editor, who dates his preface
from St. John's College, Cambridge, was induced to abridge and
digeft the elementary parts of that work into a regular fyftem; and

1

to arrange them in such order as should best correspond with the plan
of lectures given by the tutors in that university ; not without a
view, at the same time, of adapting his performance to the use of
others who may wish to be instructed in the first principles of optics.
The Editor appears to have executed this talk with judgment; and
his demonstrations are fufficiently perspicuous to be understood by
those who are acquainted with the mere rudiments of geometry,
Art. 17. Description of an Engine for dividing Mathematical In-

fruments. By Mr. John Ramsden, . Mathematical Instrument-
Maker. Published by Order of the Commissioners of Longitude,
410. 55. Nourse. 1777.

The Commissioners of Longitude having, on certain conditions,
paid Mr. Ramsden the sum of 615!. as a reward for the improve-
ments made by him in the art of dividing mathematical inftruments,
by means of a particular engine, and for assigning over to them the
right and property of the said engine, for the use of the Public: Mr.
Ramsden has, in this pamphlet, given a full description of the ma.
chine, and of the manner of using it; together with a description of
another engine, by which the endless

screw, which is a principal part
of the dividing engine, is made. These descriptions are illustrated
by four plates, in which the different parts of the apparatus are
gelineared on a very large scale.
Art. 18. A Discourse on the Invention and Improvements of the

Reflelling Telefcope, delivered before the Royal Society, Nov. 30,
1777. By Sir John Pringle, Baronet, President. 46o. 1 s. 6 d.
1778.
Sir Godfrey Copley's prize medal having been adjudged to Mr.
Mudge for his excellent paper containing directions for making the
best composition for the metals of reflecting telescopes, and for grind-
ing and polishing the great Speculum, and giving it the true para-
bolic form ; the President gives a concise history of the invention of
that noble instrument; and fails not to bestow on Mr. Mudge those
praises to which he seems so juftly intitled, for the improvements he
has made in the different processes that relate to it, and for his disa
interefed and liberal communication of them to the Public.
Ara 19. A Treatise concerning Porisins. By Robert Simson,

M. D. In which the Author hopes that the Doctrine of Parism is
fufficiently explained, and, for the future, will be safe from Ob-
livion. Translated from che Latin' by John Lawson, B. D. 410.
2 s. 6 d. Printed at Canterbury, and sold in London by Nourse.
1777

The porisms of Euclid, contained in three books, were a carious collection of many things which related to the analysis of the more difficult and general problems, and were distinguished, according to Pappus's account of their nature, from theorems in which something was proposed to be demonstrated, and from problems in which something was proposed to be constructed, as in these something was proposed to be investigated. Nothing remains in the works of the ancient geometers concerning this subject besides what Pappus has preserved in his mathematical collections. The celebrated D. Gregory, in the last page of his preface to Euclid's works, expresses his opinion, " that it would not be difficult in some measure to restore the porisms, when the Greck text of Pappus Mould see the light ;''

bus

B.y.

Ros.

but Dr. Halley, after having published this Greek text in as correa
a state as poflible, despairs of applying the information it contains
to any important and useful purpose. Pappus's general proposition
is very imperfedly and obscurely stated ; the first porism of the firft
book is the only one which he has preserved entire ; and on this ac-
count mathematicians were discouraged from pursuing an inquiry
into a subject, of which there were only fome few confufed traces re-
maining. However Dr. R. Simson undertook the difficult and labo-
rious investigation, and succeeded beyond his own expectations. The
firft fpecimen of his labour in this way was published in the Phil.
Tranf. for 1923, No. 377. See Abridg. vol. vi. part 1, p. 76, &c.
Fe afterwards pursued the inguiry, and in a posthumous work which,
among other pieces, was printed at the private expence of the Earí
Scanhope, premised some easy porisms to the explication given of
them by Pappus, and sobjoined such of Euclid's porisms as he could
diftinguit to be his ; to which he added several other propositions
of a unilar nature. The publication before us is a translation of
part of this work, which Mr. Lawson has undertaken with a view of
making it more generally known : and he proposes to compleat his
design in three other numbers of the fame kind, if he meets with
fufficient encouragement merely to defray the necessary expence at-
tending the publication.

GEOGRAPHY.
Art. 20. Geographical Exercises, calculated to facilitate the Study

of Geography, and by an expeditious Method to imprint a Know-
ledge of the Science on the Minds of Youth. With a concise In-
troduction, explaining the Principles of Geography. By William
Faden. Folio.

15 s. Printed for the Proprietor, Successor to the late Mr. Jeffries, near Charing Cross.

These Exercises conilt of nine maps, judiciously selected and neatly engraved ; and of as many corresponding theets, with the fcules of longitude and latitude, together with the meridians and latitudes upon them; which are to be filled up by the scholar with the coails, boundaries, rivers, provinces, &c. of the opposite map. The w zility of exerciting young persors in drawing maps is suficiently evident: and this performance may contribute much to facilitate the acquisition of a science which it is shameful to be ignorant of,

POLITICA L.
Art. 21. Two Letters from Mr. Burke to Gentlemen in the City of

Brittol on the Bills now depending in Parliament, relative to the
Trade of Ireland. 8vo. 13. Dodiley. 1778.

Mr. Burke having concurred with administration, in favour of the : bills above alluded to, on general (perhaps too general] principles of

fair, open, national commerce, (considering the Irish as a part of ourfelves) and regardless of the particular objections * made to those bills by the merchants of Bristol, Liverpool, Glasgow, &c.-Murmurs were, confequently excited amongit his conftituents, of the tirit mentioned

• What those objeâions are, does not particularly appear in these Letters ; but they may be seen in every news paper; and they seem to have weighe fufficient to merit Mr. B.'s utmoit attention,

Bin.g.

city,

city, who complained that they could not have him for their advocate.
On this occasion, Mr. B. deemed it necessary, not only to affert
the independency of his opinion, and to evince the rectitude of the
vote he had given, but to endeavour, also, to convince the gentlemen
of Bristol, that the natural tendency of the Bills in question, would
be for their † benent, on the whole, as well as that of Ireland : Since
Bristol, from its peculiarly advantageous situation for commerce with
Ireland, must ever find its be account in the prosperity of that
Island, -in proportion as it is better to crade with a rich and flourish-
ing country than with a poor one.-Mr. B. has thrown out a variety of
remarks drawn from more general considerations; especially from the
present critical fituation of government, &c. for which we refer to
the letters, at length.
Art. 22. A Letter to the 1Vorshipful the Dean of Guild, and the

Merchants and Manufacturers of the City of Glaigow, upon their
Oppofision to the Irish Bills. 8vo. 6d. Fielding and Walker.

A tharp invective against the " Men of Glasgow,” for their opposi-
tion to the Irish Bills. The writer takes the liberty to remind them
of, - what he supposes them to have forgotten,-the former poverty
of Scotland, till that country experienced the benefit of those lauda-
ble principles of free, unrestrained trade, to which the merchants, &c.
of Glasgow now seem to have so many objections, when it is proposed
that other parts of his majesty's dominions should, in their turn, re-
ceive the like advantages. There is more of facire than of arga-
ment in this little piece ; the author of which has contrived to intro-
duce the following itory, of a proclamation made, in former times, by
the Town-Cryer of Innerkeithing, viz.

“ Awe ye gude fowk o' the toun of Innerkeithen; this is to let
ye wat that there is cum to this toun the day, a beast called a lamb!
the laird o' che manor is to ha' the first quarter, the provell is co hia’
the second quarter, and the minister is to ha’ the third quarier:
the heed and the harigals.gaes to the baillie. I Johnny Bell is to ha'
twa (ma' puddings for cawing; but if nae body ipiers for the lave o'
the beast, it will no' be kill'd the day.”

The author says he was furnished with the foregoing notable oration,
• by respectable authority ;'-but he modeitly adds, ' I vouch noc
for its truth.'-How many good jefts are fpoilt by that ugly word
faat!
Art. 23. A Letter to the Hon. Mr. Ch— 5 F-x, upon his pro.

ceeding in Pi, on that memorable Day, Feb. 176 1778,
8vo. Fielding and Walker.

Arraigns the conduct, and questions the abilities of Mr. Fox;
grounding his impeachment principally on what the Leiter Writes
terms the miserable speech of this celebrated young orator, 'in reply
to the minister, when the latter publicly made that fuil and memoran
ble recantation of his political errors, in the unhallowed chapel of
St. Stephen.'-Good heaven! says he, what materials were'tbere
bere (you see, reader, it is but an bere and there kind of flyle in

+ • It is for you, and for your intereft, as a dear, cheitha', and respected part of a valuable wbule, that i have taken my fac ia shes quellion

IS.

which this gentleman writes ) for one of the most masterly Philippies that ever touched or acted upon the heads and hearts, of men ! And the ground, throughout so strong and obvious, it seems to have needed but small ability or art to seize it. Real patriotic feelings could Kot potsibly have resisted taking it. Your private line of interetted pursuit, one cannot but think, of course, would di&tate ic : and your personal animosity to the man could leave no room to doubt, how much you wished him down: and yet you let this great occasion flip. To what can we ascribe this ?-How poslibly account for che frange congratulating strain, for acquiefcing language and promised fupe port in the very moment of all others that called for your most powerful invigorated exertions, that demanded the most animated, violent, redoubled efforts of opposition. Instead of this, it is remarked, Mr. F. actually, himself, most unaccountably aided the very minifter, whose removal had been the fingle object of his (Mr. F.'s) political life, and concurred in suffering OPPOSITION to be the dupe of ministerial jockeyship, to a degree beyond all power of belief. The au. thor concludes, your letting go bye fo palpable an opening, [to push the minister from his ftation) can only be imputed to the want of necessary, quick, political, discernment, to your incapacity, your unfitness for that character and part which your puny, ill-supported ambition led you vainly to affumi.'

On this point, and on the politics of the times, particularly the American revolt, the author enlarges, through forty pages, in which we meet with some notable observations, expressed in a manner fingularly uncouth and unpleasing. In principle, he is anti-ministerial, but not violent. He condemns the condud of administration, as unhappily founded on one or both of the following capital deficiencies--the want of information, with respect to the state of America, or, what is fill worse, an ignorance of buman nature : which he endeavours to evince by arguments drawn from notorious fa&ts.- With refpect, however, to the gentleman to whom these observations are immediately addressed, he takes leave of him in the following terms:

• Abilities, Sir, undoubtedly you poffess-but I cannot say that you have convinced me you have to that degree, or to that general extent, which your friends would seem to give you credit for. Appearing earlier than most characters, and the education you had received haviog been directed principally to the line of parliament, and under the immediate controul of one who felt not only a warm interest in die recting it, but who was fully competent to the talk of giving it, being himself both an able politician, and a successful speaker in parliament-men were well and favourably disposed to receive you upon the mere credit of your master, and you came forth with uncommon expectations and eclat-with every advantage too, for many of the old respectable speakers were gone off - the remainder few retiring falt-and the disipated manners and idle turn of the times furnished no supply to these ;—and thus ftanding in a manner alone and fingle-you appeared with unusual luftre-was regarded as a prodigy of parts. Your style of speaking marked evidently the school in which you ftudied and proved the wonderous pains and care with which you had been taught. But circumstances, partly of your own producing, partly in the course of nature, food left you to yourself;