[ 494 ] 
extenfive motion when going to deep than by external impreffions in the day-time, 
ibid. EfFe&s produced on a leaf by the burning lens, ibid. And the electrical 
jfhock, p. 360. Two other fpecies of this genus mentioned by Linnaeus, ibid. 
1 
B 
Balloons, the cheapeft method of filling them with the lighted: inflammable air, p. 297. 
Barhadoes , etfeCts of the dreadful hurricane there in 1780, p. 334. The aftinia, or a 
fpecies of animal flower, then found in confiderable numbers on thatcoaft, p. 335. 
Barker , rev.. Robert, B. D. See Stag's Head and Horns . 
• Thomas, Efq. See Barometer , &c. 
Barometer, Tbertnometer , and Rain, AbftraCt of a Regifter of, at Lyndon, in Rutland, in 
1784. By Thomas Barker, Efq. Alfo of the Rain at South Lambeth, Surrey 5 and 
at Selbourn and Fyfield, Hampshire, p. 481. 
Safe, account of the Meafurement of a bafe on Hounflow Heath, by Major-general 
William Roy, p. 38;. Introduction, ibid. — 390. The author’s acknowledgements of the 
affiftance of feveral fcientific gentlemen, p. 389. 391. 417. 425. Particularly of the 
worthy Prefident of the Royal Society, p. 423. 458. Choice of the bafe, tab. XVI. 
p. 390. Firft tracing of the bafe, and clearing of the ground, tab. XVI. p. 391. Sol- 
diers preferred to country labourers, and why, ibid. A detachment encamped near 
Hanworth Summer-houfe, ibid. Clearing of the firft feCtion of the bafe, p. 392. 
Tracing of the fecond and third feCtions, p. 393. Half the foldiers quartered in the 
neighbouring villages to clear the third feftion, while the remainder fmoothed the 
fecond, ibid. Inftruments made ufe of in the firft and fecond meafurements, p. 394, 
Steel chain, tab. XVII. ibid. Conftruction of the chain, ibid. Alteration of the 
chain, p. 393. Deal rods, tab. XVIII. p. 397. Different opinions concerning the 
beft method of applying rods in meafurement, p. 398 . Meafuring rods and ftandard rod 
defcribed, p. 399. Brafs llandard fcale, and method of laying off the lengths of the deal 
rods, p. 401. Major-General Roy’s fcale comparedwith the Society’s ftandard, p. 402. 
Manner of afcertaining the length of the deal rods with it, p. 403—403. Chefts for 
bolding the deal rods and flandards, p. 405. Stands for the meafuring rods, tab. 
XVI II. and XIX. p. 406. Method of drawing a line through the air, parallel to the 
common furface from ftation to ftation, in equal dillances of 200 yards or 600 feet, 
as in the figure at the top of tab. XVIII. p. 407. Nature of the moveable ftands 
(towards the right-hand in tab. XVIII. and XIX.) explained, p. 408. Plans of the 
two tables (towards the right-hand in tab. XVIII.) explained, ibid. Plan of one of 
the i'quare tables (towards the left-hand of tab. XVIII.) with the ends upon the fecond 
and third rods upon it in contaft explained, p. 409. Mr. Smeaton’s deal platforms, 
ftanding on pickets driven into the ground, and properly levelled (tab. XIX.) 
defcribed, p. 410. Boning telefcope and rods, tab. XVIII. p. 411. Method of 
tracing the line of 200 yards, &c. from one fixed hand to the other, ibid. Boning 
telefcope 
