Part III. Of Regular Stones. 5 1 5 
of Plates or Crujh narrowed from the middle of the Stone 
both ways, fo as to make that Figure. A fecond, Oval 
with three Hemifpherick knobs appendent 5 all plated, as 
the Globular. A fourth and fifth figur d almoft like a 
Finger. 
THUS FAR of Plated Stones. Next of thofe which 
we may call Fibrous. In the former^the Parts are anfwerable 
to the leaves in a piece of Paft-board. In thefe to the Briftles 
in xBrujh, or the Threads in a Skeine of Silk, 
THRUM-STONE,as I call it. Amianthus Lapis & Asbefti- 
nws. It grows in fhort Threads or Thrums, from about a 
I of an inch to an inch in length 5 paralleled glolfyj as fine, 
as thofe fmall fingle Threads the SilkWorm fpins 5 and 
very flexile, like Flax or Tow. Nothing anfwers it better, 
than the hard fibrous part of a large Oyfter, when 'tis ftew'd. 
Here are feveral pieces , both of White and Green. Of 
which, the latter hath the longer!: Threads, and the mod 
flexile. 
A piece of AMIANTHUS-ROCK 5 in which the Thrums 
( about * of an inch in length ) lie in Layers between feveral 
Beds of aGreenStone,in fome places of a rediih brown. 
Another, with Veins or Layers between Beds of a blewifh 
colour. 
A BASTARD-AMIANTHUS. It grows in Veins in a 
Claiy and Mundick Load , between Beds of a Greenifh 
Earth. The Threads ? d or near ? an inch long, of a glofry 
black, and brittle. Given by Mr. Coleprefi, who obferv d 
it amongft the Corni/h Mines. 
The beft is found in Cyprus and India. Of late, very 
good in fome Mines in Italy. Of which fee the Philof. 
TranfaRions. (a) It was anciently fpun, like Tow, into Sheets $ 00 Num.72 0 
in which the Bodies of Princes, laid on the Funeral Pile, 
were wrapped up, to keep them entire, when they were 
burnt, from the other aihes. Thefe Sheets were made clean, 
not by wafhing, but by burning them 5 as being infuper- 
able by the fire : from whence the Name of the Stone. 
The Art, as well as the Ufe, is thought to be gone. But 
notfo, for Sept alius (b) hath or lately had both Thread, (b)Mufeum 
Ropes, Paper, and Netted-Works all made hereof 3 and fome 
of them with his own hand. Boetius defcribes (c ) an fa ub. de 
Oyntment made of this Stone, which he highly com- Lap. & Gem, 
S f mends 
