{! iq8o ] 
Jfoufes, Sec* points at the upper terminations cf r conductors to fee u re them from 1 ’gfis- 
ring more ufeful than balls, p. 133 — 159. Rounded conductors fecure houfes againft 
the effeCls of lightning better than pointed ones, p. 245, &c. Pointed conductors 
recommended as the molt effectual for this purpofe, p. 314—317. Farther in- 
quiries refpeCiing fharp and blunt conductors, p. 801—820... 823 — 853. 855 — 860. 
999 — ioir. Defcription of houfes built with reeds in the ifland of Sumatra, 
p. 162. A defcription of the houfes at Fort Malbro’ in the fame ifland, p. 162. A 
defcription of a mod effectual method of fecuring houfes- againd fire, p. 884. See 
Fire. 
Banter, Mr. John,, on the hear,. &c tt ,, of animals and vegetables, p. 7. See Animals, 
Vegetables* 
Button, Charles, efq. on the force of fired gun-powder, and the initial velocities of can- 
non-balls, determined by experiments ; from which is alfo deduced the relation of 
the initial velocity to the weight of the fhot and the quantity of powder, , p. 50, 
See Gun-powder, His account of the calculations made from the furvey and mea- 
fures taken at Schehallien, in order to ascertain the mean denfity of the earth, p, 689, 
Miygens, his opinion concerning the communicating of motion to bodies, p. 346. 
I. 
Jails,. how infedious fevers are produced therein, p. 204, 203. 
Jamaica , the proportionable number of whites that die there annually, p. 134* 
Fee keeps water warm, p. 3 3. Is one of the word conductors of heat, ibid. n. 
Jlbao , a fmall ifland near St.. Miguel, a fine bafon in it, p. 603, 604. 
Impaft. Reflections on the communication of motion by impaCt and gravity, p. 344^ 
See Motion *, 
Infancy . Small-pox fatal in early infancy,. p. 14.3. 
irtgenboufz,y Dr. John,, his method of lighting a candle by a very moderate electrical 
fpark, p. iq -2 2. See EleSlrical. Spark*. His leCture on the EteCtrophorus, p. 1027. 
See Ele&ropborus* Okfervatious and experiments tending to confirm Dr. Ingenhoufz’s 
theory of the EleCtrophorus 3 and to fhew the impermeability of glafs to eleCtric fluid, 
p. 1049-1033.. 
Xncculation, inquiries to demondrate the advantages of it, p. 142* 143. The age when 
children fhould be inoculated, p. 143. 130. 
Infrument , defcription of one intended to find out the comparative expanfibilities of 
bodies by heat, p. 428- — 434. Mr. Le Cerf’s account of two indruments very ufeful 
for determining the perfect proportion between different moveables aCiing by levers and 
wheel and pinion, p. 930 — 998. 
Journal of a voyage to the Ead Indies in the year 1733, p. 389—416. See Fables 
Journal* of the weather, at Montreal, P..539. See Weatbtr*. Extra# of a meteorolo- 
* gicai 
