1819.] Scientific Intelligence. 391 
battery ; and may very possibly afford some valuable applications 
of it to chemical purposes. 1 am, Sir, 
Your most obedient servant, 
Tuomas GILL. 
*,* In a postscript, dated April 24, Mr. Gill adds, that Mr. 
Tuther, Philosophical Instrument Maker, High Holborn, has 
fitted up several electrical jars in this new manner, using, how- 
ever, t2n foil upon paper tor the coating around their outsides, 
instead of tinselled paper. The success has been complete ; 
the unpleasant sensations occasioned by the passage of the 
electric fluid from common jars being entirely done away ; 
whilst the most powerful effects are produced. 
i 
Though medical electricity has been administered for years in 
this country in nearly the same manner described in the dite 
ing communication, yet as the method has never, so far as I 
know, been communicated to the public, I was unwilling to with- 
hold the preceding letter, and trust that our medical electricians 
in this country will be induced by it to state the result of their 
experience on the subject.—T. 
XVI. On British Mathematical Periodical Works, with a Ma- 
thematical Query. 
(To Dr. Thomson.) 
SIR, ; London, Feb. 10, 1819. 
We have several periodical publications devoted almost exclu- 
sively to mathematical subjects, which often contain productions 
of considerable merit ; but it is much to be regretted that the 
subjects are generally of a trifling nature. The questions are 
formed without any object beyond that of ingenious exercises ; 
they betray no extended views, no attempts to advance physico- 
mathematical science, nor its application to the wants of society, 
The time and talents of the mathematician being consumed mn 
the preparation of the means, he forgets the end till it be too. 
late to consider it. How different was the course which Newton 
pursued ! 
To you, who are so well aware of the imperfect state of the 
application of mathematical inquiry to physical science and the 
useful arts, | need not state that there is abundance of subjects 
that would not only improve the student in mathematical reason- 
ing, but also exercise bis inventive faculties i another and not 
less essential part of knowledge, via. the consideration of the 
premises that ought to enter into the investigation of a physical 
roblem. It is incorrectness in this that produces’ the paradox- 
ical and unsatisfactory conclusions to be met with in every 
department of mechanical science, 
