1817.] Scientific Intelligence. 163 
is, that neither the acid nor its salts exert any action upon man-~ 
ganese. 
—<aIi— 
I think it necessary to state, by way of appendix to the above 
notice, that Berzelius, as long ago as the year 1806, in his paper 
on Sebacie Acid, published in the Afhandlingar, vol. i. p. 171, 
and translated into Gehlen’s Journal (second series), vol. ii. p. 275, 
proposed benzoic acid asa good re-agent for separating iron from 
other bodies. Mr. Hisinger, in consequence of this proposal, 
made a set of experiments in 1810 on benzoate of ammonia as a 
re-agent. The result was a conviction that it would answer very 
well as a substitute for succinate of ammonia. ‘This paper was 
published in the Afhandlingar, vol. iii. p. 152; and a translation of 
it appeared in the Philosophicai Magazine, vol. xl. p. 258.—T : 
X. Queries respecting the Trigonometrical Survey. 
(To Dr, Thomson.) 
SIR, 
I should feel obliged if you would allow me to propose two plain 
and simple queries to the gentleman who signed himself R. M. A, 
in your last number. 1. Did the determination of the length of 
the pendulum, as connected with the subject of weights and mea- 
sures, originally form one of the objects of the trigonometrical 
survey? 2. Did not the operations which are now pursuing on 
that important subject originate from the following address being 
moved in the House of Commons, by an Hon. Member of that 
House, on the 15th of March last ? 
Your humble servant, 
Portsmouth, Dec. 7, 1816. Civis. 
« That an humble address be presented to his Royal Highness the 
Prince Regent, praying that his Royal Highness will be graciously 
pleased to give directions for ascertaining the length of the pen- 
dulum vibrating seconds of time in the latitude of London, as 
compared with the standard measure in the possession of this House; 
and for determining the variations in the length of the said pen- 
dulum at the principal stations of the trigonometrical survey ex+ 
tended through Great Britain: and also for comparing the said 
standard measure with the ten millionth part of the quadrant of the 
meridian now used as the basis of linear measure on the continent 
of Europe.” Which passed without opposition. 
XI. Some additional Particulars respecting the Earthquake in 
Scotland. 
(To Dr, Thomson.) 
SIR, Relugas, Nov, 12, 1816. 
In addition to the particulars of the earthquake of Aug. 13 last, 
published in your 47th number, I beg leave to send you the follow- 
i 2 
