Fullers 
Varth. 
———_ 
Uses of ful- 
lers earth. 
‘Legal re- 
straints. 
Substitutes 
for fullers 
earth. 
Lemnian 
earth. 
Osmundic 
earth, 
different qualities naturally, and are like the above, ob- 
tained artificially, and used for different purposes. The 
former, which is deemed the best, is employed in full- 
ing the kerseymeres and finer cloths of Wiltshire and 
Gloucestershire, whilst the blue is principally sent into | 
Yorkshire for the coarser cloths. Its ‘effects on these 
cloths, is owing to the affinity which alumine has for 
greasy substances; it unites readily with them, and 
forms combinations which easily attach themselves to 
different stuffs, and thereby serve the purpose of mor- 
dants to some colours ; as is the case in the Turkey red. 
The fullers generally apply it before they use the 
soap. It may be used also instead of soap on board of 
ship, ‘to wash linen or the hands with salt water, with 
which it is well known soap does not unite. ; 
The legal restrictions on the exportation of fullers 
earth, may be found in the 12 Car. II. 13 and 14 Car. 
II.; 9 and 10 William IIL. ¢.40; 6 Geo. I. c. 21. § 22. 
The penalties are so enormous, that foreign chemists 
‘turned their attention to discover substitutes for fullers 
earth. Cronstedt describes only the lithomarge of 
Osmund, Tartary, and Lemnos ; the Hampshire fullers 
earth not having come to his hands, probably on ac- 
count of the severe penalties imposed by the English 
legislature on its exportation. Bergman examined them 
all except the second, which is the keffekil of the Crim 
Tartars, who are said to use it instead of soap, and 
which he was not provided with a sample. Wiegleb, 
in Crell’s Journal, quoted by Kirwan, found that it 
consists of equal of magnesia and silex. 
The Lemnian earth, so called as being found in Lem- 
nos, was highly esteemed for many centuries, for its 
supposed medical virtues, and till lately sold in Europe 
under the seal of the grand signior, (hence called terra 
sigillata,) has the external appearance of clay, with a 
smooth surface, resembling agate,’ especially in its re- 
‘cent fractures, which are usually either concave or con~ 
vex. It may be scraped with the nail, is composed of 
impalpable particles, though a little gritty between 
the teeth, under which it feels like tallow. When im- 
mersed in water, it is spontaneously divided into small 
pieces, with a slight crackling noise, but they do not 
become so small as to be invisible or impalpable ; pul- 
verization and boiling in water diffuse it in the fluid, 
which passes almost perfectly clear through double fil- 
tering paper. This earth removes impurities like soap, 
though it affords no froth. 
The Osmundic earth comes from Osmund, in the 
parish of Rutwick, in East Dalecarlia. It colour is 
grey like cinders ; its surface rough, and as if greased; 
it is harder than the Lemnian earth, breaks into 
angular pieces, adheres strongly to the lip, and is more 
gritty between the teeth than that earth: in water it 
separates into smaller particles, and is detergent. By 
the humid analysis, Bergman found the constituent 
parts of the two foregoing earths as follows: 
Lemnian earth. 
Sil 5 1) cviogig pal TREN, Ae elay 
‘Carbonate oflime .0. 2. 0.0.0.0. (54 
Magmesias So! yo 4) 50, GREY Tp MAGE 
Alumirie © .,.cy* yitte ave yee sen Pag 
Oxide tof fron =i!) Ages rig hy ty ea HR 
Moist volatile matter capable of being ex- 
pelled by drying. . 2... . 26 
100 
28 FULLERS EARTH. 
: Osmundic earth. 
White siliedous‘powier <7 .¢y'ira chair 60. 
Eime o% qo eet, aos vipa. : oe ae 
Mapnesia 01580) 90 Suliitpuiicn! ae 
Alamine' pp Legh. ge getiga sy . ah 
Oxide'‘of iron: Vee 9 oo lies GmoeinT Ay 
Moist volatile matter . . . . 
100 
“Amongst the foreign varieties of lith 
ticularly: in this place, where substitutes are trea 
For this, however, we must refer to the inning 
of the article, and this head will be concluded by in- 
troducing a substance that is very generally found 
both in Great Britain and abroad. Fullers earth, we 
have seen, from the general results, is alumine, com- 
bined with very fine silex ; it is essential to this earth 
that the particles of silica should be very fine, other- 
wise they would cut the fine cloth ; hence the object 
in washing over the fullers earth mentioned in a pre- 
ceding paragraph. It is owing to the strong affinity, as 
noted before, which alumine has for greasy substances, 
that it is so useful in scouring cloth; hence pipe clay, 
the cimolian earth mentioned in the beginning of this 
article, is frequently used for the same purpose ; and it 
may also be concluded, that any clay possessed of this’ 
property may be considered, in its uses, as fullers 
earth ; for it is the alumine alone which acts upon the 
grease in the cloth. 
that it should contribute to the washing away all im- 
purities, and promote that curling and intermixture of 
the hairs of the woollen cloth, which thicken its tex- 
ture, and give it the desired firmness. Both probabl 
depend.on its detergent quality, that clears away all 
the unctuous matter of the wool, and renders its parts 
capable of becoming more perfectly entangled by the 
mechanical action of fulling ; an effect not so likely to 
take place where the fibres or hairs are di 
to slide easily over each other. The detergent power 
resides in all clays, but is doubtless greatly increased ‘ 
by the siliceous earth, which may be considered as the 
brush, while the clay serves as the soap. This is fa- 
miliarly shewn by the common practice of adding sand 
to soap, which renders it much more detergent, but, at 
the same time more capable of injuring the substances 
to which it is applied, and that more especially when 
the sand is course. Fullers earth. is bad if the sand 
be not exceedingly fine, and the superior excellence of 
the Hampshire earth seems to depend more on the 
fineness of its parts, than on their p ions, ‘as is 
shewn by the experiment of boiling it in water, after 
which it passes more plentifully through the filter than 
es of the other kinds of lithomarge. («) 
ULMINATING Pownenrs is a name given to those 
chemical compounds which are decomposed with such 
' rapidity as to produce areport, with other signs of vio« 
lence. The most conspicuous of these bodies are the 
ammoniurets of gold, silver, and mercury ; the preci- 
pore formed by alcohol from nitrate of mercury, which 
been called fulminating mercury, and the powder 
formed with potash, nitre, and eulohary called pulvis 
Sulminans. _ 
The first of these compounds, viz. ammoniuret of Fulminat-_ 
gold, is prepared by dissolving gold in a mixture of ing gold, 
equal parts of nitric and muriatic acids ; dilute the so- 
: ythe Fale 7 
fullers earth of Saxony ought not to be forgotten, on Saxony. 
The ae required in good fullers earth are, ’ 
8 
: 
