: ADVERTISEMENT. 
ee seventeen years have elapsed since Tur PutLosopnicaL 
JourNAL was commenced by Mr. Nicwovson, and sixteen since the 
appearance of the first number of the PHILosopHICAL MaGazine, 
During this period the sciences and arts have made the most rapid 
progress. Numerous philosophical and mechanical instruments and ma-* 
chines have been invented and improved ;---the theory and practice of 
astronomy has been greatly advanced ;---new planets have been dis- 
covered, and the structure of the sun more clearly ascertained. The 
rays of light have been subjected to new experiments, which have de- 
monstrated their separate and distinct powers of illuminating and of 
heating; and that wonderful property upon which the phenomena of 
the island crystal depend, but which is now known to be inherent in 
both kinds of rays, and universally operative in all the cases of re- 
flection and refraction. Chemistry has a second time within the above 
period become a new science---by the discovery of the effects of gal- 
vanism upon its processes, and the development of elementary sub- 
stances of higher simplicity than were before known;---by the definite 
proportions of the component parts of bodies ;---by the laws of elective 
attractions and of crystalline forms ;---and, even to a certain extent, 
by a discovery of the remoter causes of those laws and forms. The 
cultivators of the sciences, the directors of the operations of the arts, 
with public institutions and societies, have become every year more 
numerous and rapid in their increase ; at the same time that new roads, 
bridges, canals, and other national works, as well as private under- 
takings, have been every where established to an unprecedented extent. 
Under such circumstances of national vigour and exertion, we have 
found that the situation of Journalists of the discoveries and improve- 
ments made by philosophers and men of research in every part of the 
civilized world, is most honourable and truly gratifying. Public ap- 
probation, private friendship, and a reasonable remuneration, have con- 
stituted our reward. Upon many occasions, however, our correspon- 
dents have complained that the same academical papers, and articles 
of.information, have been printed in both J ournals; and they have, in 
their separate letters, requested us to consult together upon some means 
of remedying this inconvenience, and increased expense upon many 
of our readers. But it seemed impossible to obviate this inconvenience 
in two distinct works ; both equally under engagements to present to 
the public every thing that might prove new, interesting, and valuable. 
We have conferred upon this and other considerations which might 
render our intercourse with the public more effectually useful; and 
the result of our deliberations has been that it would certainly be best 
that we should unite, and that the joint product of our exertions and 
our correspondence should be consolidated in one periodical work ; 
affording all that has hitherto been considered as desirable in the plans 
and conduct of-both ; but free from the objection just stated, and per- 
haps one or two more upon which it is needless ¢o enlarge. 
The Philosophical Journal will henceforth be discontinued; and The 
Philosophical Magazine will be conducted by Witi1am NicioLson 
and ALEXANDER TILLocH, in the same manner as it has always been 
carried on; but with every attention to improvement which the joint 
exertions of the Editors, and the communications of their friends and 
correspondents can afford. 
Communications, addressed to the Editors, Picket Place, Temple 
Bar, will meet with due attention. 
London, Dec, $1, 1813, 
VoL. 42. a 
