A 
• JOURNAL 
OF 
NATURAL PHILOSOPHY, CHEMISTRY, 
AND 
THE ARTS. 
JULY a 1813. 
ARTICLE I. 
A Theory of the Tides, including the Consideration of Resist* 
ance. By a Correspondent , E. F. G. H. 
[The author of these investigations is sensible that they are 
not altogether so explicitly and demonstratively detailed as 
could be desired j they were not written with any immediate 
view to publication $ but, as they contain some new results, 
and may possibly lead to new methods of calculation, he 
thinks it better that they should be printed in an imperfect form a 
than that they should be wholly lost, which is the only alterna* 
tive compatible with his present engagements. He does not 
apologize to an author from whom he has borrowed some f 
ideas, because all those, who are sufficiently interested in the 
subject to study this essay, are probably already acquainted 
with that author’s works.] 
Theorem A. Fig. 1. Elate IV. 
I F the point of suspension (A) of a pendulum (AB) be Forced vibra- 
made to vibrate in a regular manner, that is, according to a pen ' 
the law of cycloidal vibrations, the pendulum itself may also 
vibrate regularly in the same time, provided that the extent of 
its vibrations (BC) be to that of the vibrations of the point of 
Von. XXXV,— No. 163. L sus. 
