86 BOLE. -LEMNIAN EARTH. 
would float in water. He describes them to have been 
formed of a spongy kind of earth, and to have had some 
resemblance to pumice stone, which he says might per- 
haps be applied to the same purposes as these bricks, 
if it could be obtained and wrought in sufficient quan- 
tity. Bricks of similar description have lately oeen 
made of a mineral substance found near Sienna, in 
Italy, and which is supposed to be meerschaum. 
A kind of meerschaum has lately been discovered, 
in veins, in the serpentine (132) of Cornwall. 
127. BOLE is an earthy mineral, of yellowish or reddish 
"brown colour, soft, and somewhat unctuous to the touch, and 
generally found in a massive state. 
It exhibits internally a glimmering lustre ; and, when put 
into water, immediately absorbs it, and breaks down into small 
pieces with a crackling noise. This mineral is farther distin- 
guished by its fracture being conchoidal, or appearing some- 
what like the impression of a shell; and by its adhering 
strongly to the tongue. 
Although bole is at present little used except as a 
basis of tooth powder, and a coarse kind of paint, it 
was formerly considered an important article in medi- 
cine, and used as an astringent. We are informed that 
tobacco pipes are sometimes made of this mineral ; and 
that it is employed as an ingredient in the glaze of some 
kinds of earthen ware. 
It is chiefly imported from the Levant ; though it 
has als 4 been found in considerable beds in Silesia and 
Saxony. 
128. LEMNIAN EARTH is a kind of bole of yellowish 
grey, or yellowish white colour, sometimes marbled with rust- 
like spots. 
It is distinguished from bole by being dry and not unctuous 
to the touch, dull internally, adhering slightly to the tongue, 
and its fracture being earthy. 
With the ancients this mineral was considered an al* 
most invaluable medicine. They procured it chiefly 
