™ 
G48 =—- Retrofped? of Domoftic Literature.— Mathematics, Wri 
vered during the long {pace of thirty 
years. 
<¢ Elements of natural Philofophy;” ex- 
plaining the Laws and Principles of At- 
traction, Gravitation, Mechanics, &c. &c. 
with a general View of the folar Syttem ; 
adapted to public and private Inftruc- 
tion. | 
This is a very ufeful work, and has 
the rare recommendation alfo of being a 
cheap one: the writer ftates, in his pre- 
face, that he does not aim at any thing 
more than to colleét and methodize thofe 
truths which have been demonitrated by 
therefearches of the philofopher, and to 
render them plain and evident to thote 
whofe timeand education will not enable 
them to draw their information from ori- 
ginal fources. This tafk is performed in 
avery pleafing and fatisfactory manner: 
wooden cuts are given in the bady of the 
page, defcriptive of a variety of machines 
and experiments, which are detailedin a 
clear and able manner. 
The fifth and fixth volumes of the 
¢ Scientific Dialogues’ are  publifhed ; 
treating, the former of optics and mag- 
netifm, the latter of ele€tricity and Gal- 
vanifm. It was originally intended to 
comprehend an Introduétion to Chemif- 
try; but the author obferves that tlis is 
a branch of f{cience now become fo very 
interefting, and the ftudy of it fo gene- 
ral, that it would have been unpardon- 
able not to have devoted to it a more am- 
ple {pace than the limits of thefe volumes 
would allow. He has, therefore, under- 
taken to furnifh a feparate work on this 
fubje&t, to be comprifed in two volumes, 
fimilar in fize with the Scientific Dia- 
logus. The plates to this work, fome 
by Lowry and fome by Skelton, are beau- 
tiful: we infer from one of the plates to 
vol. 6, that the work itfelf is the pro- 
duction of the Rev. J. Joyce. It does 
him great credit. 
A fecond edition, enlarged, is publith- 
ed of Profeffor Phayrair’s ‘* Elements 
of Geometry.” 
<< 4 Differtationon the Influence of Gra- 
witation, confidered asa mechanic Power ;” 
explaining the Reafon why the cffcctive 
Power of the fame Quantity of Matter in 
defcending the fame Height is twice as 
great in its uniform Defcent as in its ac- 
celerated Fall; and why twice the Quan- 
tity of Refiftance is required to bring a 
Pendulum to Reft when gradually ap- 
plied to it, as when applied at once to its 
loweft Point. By A. Cummina, F.R.S. 
&c. 
Perpetual motion is to mechanics the 
/ 
philofopher’s ftone: in this very ingeni- 
ous eflay Mr. Cumming has fhewn, very 
fatistactorily, the impoffibility of obtains 
ing it by an examination of the effective 
power of gravity. 
This very accurate mechanic has alfo 
publithed ** Obferwations on the Effects 
which Carriage Wheels, with Rims of 
diferent Shapes, have on Roads.” 
Our heavice and largelt waggons have 
conical wheels: cylindrical rims have a 
conftant tendency to preezed in a ftraighe 
direction, whilft the conical rims have a 
natural tendency to revolve if a circular 
dire€tion round their conical centers. To 
counteract this tendency, therefore, acon- 
ftant force muft be employed, and, of 
courfe, diverted from its preper applica. 
tion. Every point’on the furface*of a 
cylinder has the fame rotatory motion: a 
cone is a feries of concentric circles, hav- 
ing different radii, and its points have dif- 
ferent rotatory motions, according to the 
diftance of the refpeétive circles from the 
apex of the cone. Butif a conftant force 
is requifite to confine the conical rims in 
a ftraight courfe, it is obvious that an un- 
neceflary degree of friction takes place at 
the rim and at the axis, and that the la- 
bour of the draft horfe is very much in- 
creafed by the fuperfluous refiftance. 
The Rev. T. Newron has attempt- 
ed, not unfuccelsfully, “ Az Ilufiration 
of Sir Ifaac Newton's Method of Reafons 
ing by prime and ultimate Ratios; com- 
prehending the firft Setion of his Princi- 
pia, and as much of the fecond and third 
Se&tions as is neceflary to explain the 
Motion of the heavenly Bodies. 
Theauthor was formerly a tutorat Cam- 
bridge, and the difficulty he found in ex- 
plaining to his pupils, in the ufual man- 
ner, the reafoning of Sir Ifaac Newton, 
led him to difcover and adopt a more in- 
_telligible method. 
_ The fifth volume is publithed of © Scrip- 
tores Logarithmici;” or a Colleétion of 
feveral curious Traéts on the Nazure and ~ 
Conftruétion of Logarithms. It contains 
fourteen nuinbers, of which an ample ac- | 
count is given, in an elaborate and perfpi- — 
cuvus preface, by Baron MasERES. 
The Royal Society has publifhed the 
fecond part of their ‘* Philofophical Tranf- 
ations for the Year 1804.’ It contains, 
among other valuable papers, fome ob. 
fervations oh bafalt, and on the tranfition 
from the vitreous to the ftoney texture, 
which occurs in the gradual refrigeration 
of melted bafalt, by GREGORY WatTT, 
Efq. | 
This gentleman, whole early years ac- 
quired 
