quor prepared with afhes. Now, every 
chemilt knows that this liquor will confatt 
of the folution of the ufual falts, produced 
by receiving the oxygenated muriatic acid 
gas into @ folution of pot ath, together 
with a quantity of oxygenated muriatic 
acid, in an uncombined ftate. It is like- 
wife perfectly well known, that fuch li- 
quor will deftroy dyed colours. This 
liquor therefore with which Mr. Rupp 
compares that made of lime, is totally 
unfit for bleaching any kinds of goods 
into which dyed colours enter, and con- 
fequently, wherever thefe are to be bleach- 
ed, his ftatement does not apply. The 
fact is, that where fuch goods are bleach- 
ed, three times this quantity of afhes, or 
even more, is univerfally ufed. 
Wherever, therefore, fuch coloured goods 
are to be bleached (and fuch goods con- 
ftitute a great proportion of the cotton 
manufactory in Britain), his ftatement 
will not apply. But befides this, it is 
to be obferved (as Mr. Rupp would 
have feen if he had read the {pecification, 
er applied for information to any of the 
refpectabJe bleachers’ in his own neigh- 
bourhood who ufe the procefs, and who 
keep their doing fo ne fecret), that the 
introduétion of common falt along with 
the lime in my procefs, was merely to in- 
creafe the {pecific gravity of. the water, 
for the better fufpenfion of the lime; and 
asan addition, that afterwards might or 
might not be made, as experience fhould 
- direét. The falt, therefore, is now re-, 
~~ omitted ; mere agitation being 
ound perfectly fuficient to keep the lime 
in fufpenfion. With this. correétion, 
therefore, even with Mr. Rupp’s pro- 
portion of afhes, the comparative value 
of this part of the ingredients of the li- 
quor made with afhes, and that made 
with lime, will be as 3s. 9d. to 7d. and 
in-all cafes, the faving brought about by 
ufing the lime liquor in preference to that 
made with afhes, will beequal to the dif- 
ference of price between the afhes and 
lime, and even fome diminution of the 
quantity of lime may with fafety be ad- 
mitted... With regard to the additional 
labour in preparing the liquor, it is a 
mere trifle. A workman mutt attend 
while the liquor with afhes is preparing ; 
when he makes the liquor with lime, he 
needs only to add to his ufual attendance 
a very moderate portion of bodily labour, 
applied to agitate the liquor in the re- 
ceiver. Several of the. bleachers in this 
country have now even faved him this, 
by conneGting their agitators with their 
plath-mill, or other moving machinery, 
Mr, Tennant’s Defence of his Bleaching Liguor. 
405 
Mr. Rurp next attempts to prove, 
‘that both this and the ufual lijuor pre- 
pared with afhes, are inferior to the dim- 
ple oxygenated muriatic acid for the pur= 
pofes of bleaching. } 
I have already ftated, that bleaching 
liquor, containing the ufual falts formed. 
from the oxygenated muriatic acid gas’ 
and pot afh, together with. uncombined: 
oxygenated muriatic acid, was totally 
unfit for bleaching goods which contained: 
dyed colours. The fimple oxygenated 
‘acid is confequently totally unfit for 
bleaching fuch goods. If, therefore, we 
fet afide the liquor made with a full pro-. 
portion of afhes and alfo that made with - 
lime, a great proportion of the cotton 
goods manufactured in Lancafhire, and. 
almoft the whole of the Glafgow fabrics 
will be deprived of this great improve- 
ment in the art of bleaching. It muft be 
allowed, therefore, that even on the fup- 
pofition of the inferiority of the power, 
pofleffed by the alkaline and lime liquors,, 
they muft be retained for the purpofes of 
bleaching goods containing dyed colours. 
Alfo, that we muft prefer lime to the al. 
kaline liquor, becaufe it is cheaper, by 
the difference of price between. the alkali 
and lime, and that this difference will be: 
very confiderable, becaufe a very. large 
proportion of afhes muft be ufed, inorder 
to preferve the dyed ccleurs: that enter 
the compofition of the goods. bight 
Tt till remains to determine, whether 
the fimple oxygenated muriatic acid. is. 
more applicable to the purpofes of bleach- 
ing, where no dyed colours enter the - 
fabric, than alkaline or lime liquor. — 
In favour of the fimple oxygenated . 
acid, Mr. Rupp quotes his experiments 
in the laft vol. of the ‘* Manchefter Me- 
moirs.’ Where experiments are made only 
on a few grains, and where we have no 
better teft of their relative differences or” 
agreements, than a difference of colour 
induced by a few drops, as it appears te 
the eye of an experimenter, perhaps, from: 
fome preconceived theory, inclined to fa- 
vour a particular conclufion, 1 would’ 
build but little on fuch experiments ;: if- 
we add to this, the great danger to the 
fabric, univerfally allowed by bleachers,’ 
in every attempt made with ‘the. fimple 
oxygenated acid, either in a fluid, or ga- 
zeous form; the impoflibility of work-) . 
men operating with it on account of its - 
fuffocating vapours, and the doubtfulnefs 
of overcoming that, even by Mr. Rupp’s 
ingenious contrivance (for he cannot 
fuppofe, that a bleacher can calculate fo 
exactly, as to have exhaulted the oxyge- 
nated - 
