398 PRE PRI 
quantity and weight of water contained in a 
full pipe of any given height and diameter of 
bore; and confequently to find what degree 
of power would be required to woik acommob 
pump, or any other hydraulic engine, when 
the diameter of the pump-bore, and the height 
to which the water is to be raifed therein, are 
given - - Fergufon 
Precious Stones. Some remarks on the precious 
Rone called the turquoife Mortimer 
- — - — — Some obfervations upon gems or pre- 
cious hones ; more particularly fuch as the 
ancients ufed to engrave upon Dinghy 
Precipices or Cliffs. Extrad of a letter con- 
taining obfervations on the precipices and cliffs 
on the north-eaft coaft of Norfolk 
Tranf. 
LY 61 
XLIV 429 
— 502 
Arderon 
Preservation of Bodies. See Death. 
Pressure. Some experiments and obfervations on 
the force of the prefTure of the water at great 
depths - r- Anon . 
Prickleback. Abftrad oF a letter concerning fo me 
obfervations made on the banfticle or prickle- 
back, and alfo on fifli in general Arderon 
Prickly Pear. The efFeds of the opuntia, or 
prickly pear, and of the indigo plant in colour- 
ing the juices of living animals Baker 
Printing. That Coftevus firft invented printing 
1430 - - Ellis 
• Some obfervations concerning the invention and 
progrefs of printing to 1465 - Anon . 
An effay on the invention of printing, by John 
Bagford ; with an account of his colledions 
for the fame - Wanley 
► An account of Mr. Le Blon’s principles of 
printing in imitation of paintings, and of 
weaving of tapeflry in the fame manner as bro- 
cades - - Mortimer 
The description of an antique metal ftamp, in 
the coliedion of the Duke of Richmond, being 
one of the inftances how near the Romans had 
arrived to the art of priming; with fome re- 
marks - - Mortimer 
Prism. An account of rings, confining of all the 
prifmatic colours, made by eledrical explofions 
on the lurface of pieces of metal Frieftley 
— 275 
XVII 504 
XLIV’ 424 
L 296 
XXIII 1416 
~ 1507 
XXV 2397 
XXXVII 10] 
XL 388 
LVIII 68 
Abridg. 
x6 33 
— 610 
— 5 8 9 
I 521 
XL 872 
V 2 11 
12 
— - l8 
VI 469 
IX 407 
— — Aa 
