pit-coal, the colour rather greyer, very friable, and, when liquid, of a jet black 
colour, p. 6;. Some parts of the Curface covered with a thin and brittle fcoria, a 
little elevated, ibid. Calcined earth mixed with fome parts of its common fubftance, 
ibid. The bituminous fubftance c this lake fuppofed to be the bitumen a/pbaltutn 
Linncsi, p, 68. Its fubftance rendered dublile by heat; and, mixed with a little 
greafe or common pitch, is much .fed for the bottoms of flips, ibid. Suppofed to 
be a prefervative againil the Bore , ibid. 
1 Tajfefudm , productions of, p. 85. Taflefudon lower than the level of Paraghon, p. 
89. The capital of Boutan, p. 111. 
1 Thermometer , ftate of, between Bahar and Buxaduar, p. 80. State of it at Buxaduar, 
p. ST. Its fate at Punakha, p. 84. Its fate at Chepta, ibid. Its fate. at Sanha, 
p. 90. Its fate at Duina, p. 92. Its fate at Tifoolumboo, p. 97, 98. State of 
The thermometer at London during the year 1788, p. 1 14 — 138. 
Thibet, the hills in this country have, from their general appearance, frong marks of 
containing thofe fdffils which are inimical to vegetation, p. 93. Tincal, which is 
afterwards refined into Borax, is found in inexhaufibie quantities in Thibet, p. 96. 
Rock fait found in great abundance in this country, ibid. Difeafes of, p. 98 — :o6. 
Method of preparing mercury in Thibet, p. 100. The phyficians of this country do 
not treat the fmall-pox properly, their whole attention being to pieferve themfelves 
from the difeafe rather than to affift thofe who are infe&ed with it, p. 105. All 
communication with thofe who have the fmall-pox ftriflly forbidden, ibid. Hot baths 
ufed by the inhabitants of Thibet in many diforders, ibid. 
Tincal , found in Inexhaufibie quantities in Thibet, p. 96. The lake where tincal is 
collected about fifteen days journey from Tifoolumboo, ibid, Tincal depofited or 
formed in the bed of a lake ; dug up in large maffes, p. 97. Tincal is found only 
in {hallow water, on* the borders of the lake, ibid. Ufed in Thibet for folder, and 
to promote the fufion of gold and filver, ibid, 
TiJfoolumboQ , piodudtions of, p. 94, Soil, ibid. State of the thermometer at, pp. 97, 
98. The capital of Thibet, p. iri. 
Trinidad , account of a bituminous lake or plain in theifland of, p e 6^. In feveral parts 
of the woods in this ifland are hot (brings, p. 69. 
Turbin b mineral, being mixed with fulphur, produces vitriolic acid air, p. 13, See 
Sulphur, 
V. 
f id ties ) Sec. on the method of cofrefpo ident, p. 166. The method of correfpondent 
values eafily affords a refolution of the problems contained in Mr. Brigg’s or Sir 
Ifaac Newton’s method of differences, p. 177. t 
Venereal difeafe, frequent in Thibet, p. 100. Method of treating that diforder in 
Thibet, p. 101. d'd 
Vifiotu 
