D Y 1 
indigo vat} and, after it is dry, the wax oompofition is 
removed bv means of hot water. 5. Lilac, brown, and 
blackifli brown, are given by means of acetit of iron; 
the quantity of which is always proportioned to the depth 
of the (hade. For very deep colours, a lit 1 e fumach is 
added. The cotton is afterwards dyed in the ufiial man¬ 
ner with madder, and then bleached. 6. Dove-colour 
and drab, by charging the blocks with acctit of iron and 
quercitron bark. 
When different colours are to appear in the fame print, 
two or more blocks are employed, upon each of which 
that part of the print only is cut or engraved, which is 
to be of fome particular colour. Thefe are befmearcd 
with different mordants, and applied to the cloth, which 
is afterwards dyed as ufual. Suppofe, for inftance, that 
three blocks are applied to cotton; one with acetit of 
alumina, another w ith acetit of iron, a third with a mix¬ 
ture of thefe two mordants, and that the cotton is then 
dyed with quercitron baik, and bleached. The parts im¬ 
pregnated with the mordants would have the following 
colours: 
Acetit of alumina . . . Yellow, 
iron.Clive, drab, dove, 
The mixture.Olive-green, olive. 
If the cotton be dyed with madder inffead of quercitron 
bark, the print will exhibit the following colours: 
Acetit of alumina.Red, 
iron.Brown, black, 
The mixture .Purple. 
When a greater number of colours are to appear ; for 
Inftance, when thofe communicated by bark and thofe 
by madder are wanted at the fame time, mordants for 
part of the pattern are to be applied ; the cotton is then 
to be dyed in the madder-bath, and bleached ; then the 
reft of the mordants, to fill up the pattern, are added, 
and the cloth is again dyed with quercitron bark, and 
bleached. This f'econd dying does not much aft'eCt the 
madder colours; becaufe the mordants, which render 
them permanent, are already faturated. The yellow 
tinge is eafily removed by the fubfequen-t bleaching. 
Sometimes a new mordant is alfo applied to fome of the 
madder colours ; in confequence of which they receive a 
new permanent colour from the bark. After the laft 
bleaching, new colours may be added by means of the 
indigo liquor. The following table will furnilh an idea 
of the colours which may be given to cotton by thefe 
somplicated procefles: 
I. Madder dye. Colours. 
Acetit of alumina.Red, 
iron.Brown, black. 
Ditto diluted.Lilac, 
Both mixed.Purple. 
IT. Bark dye. 
Acetit of alumina.Yellow, 
iron ....... Dove, drab. 
Lilac and acetit of alumina . Olive, 
Red and acetit of alumina . Orange, 
III. Indigo dye. 
Indigo.Blue, 
Indigo and yellow.Green. 
Thus no lefs than twelve colours may be made to appear 
together in the fame print by thefe different procefles. 
It it were poftible to procure colours fufficiently perma¬ 
nent, by applying them at once to the cloth by the block 
or the pencil, as is the cafe with the mordants, the art 
of calico-printing would be brought to the greateft pof- 
fible fimplicity : but at prefent this can only be done in 
one cafe, that of indigo ; every other colour requires dy¬ 
ing. Compoiitions, indeed, may be made by previoully 
combining the dye-ftuif and the mordants. Thus yellow 
may be applied at once by employing a mixture of the 
infufion of quercitron bark and acetit of alumina; red. 
Vol. VI. No. 340. 
D Y N .109 
by mixing the fame mordant with the decodlion of alu¬ 
mina, and fo on. Unfortunately the colours thus com¬ 
municated are far inferior in permanency to thofe pro¬ 
duced when the mordant is [ revioufly combined with the 
cloth, and the dye-ftuft'afterwards applied feparately. In 
this way, therefore, are applied almoft all the fugitive 
colours of calicoes, which waffling, or even expofure to 
the air, fo commonly defttoys ; but which an act of the 
legiftature might in future prevent, by prohibiting, un¬ 
der a high penalty, the ufe of falfe and fugitive dyes. 
The following are the prefent exifting laws which re¬ 
gulate the trade of a dyer : By 3 & 4 Edw. VI. c. 2. no 
dyer may dye any cloth with orchel, or with Brazil, to 
make a faife colour in cloth, wool, &c. on pain of twenty 
{hillings. By 23 Eiiz. c. 9. dyers are to fix a feal of lead 
to cloths, with the letter M. to fnew that they ate well 
mathered, &c. or forfeit three fliiTlings and four-pence 
per yard. By 23 Geo. III. c. 15. feveral penalties are in- 
flidled on dyers, who dye any cloths deceitfully, and not 
throughout w ith vvoad, indigo, anti mather ; dying blue 
with logwood to forfeit tWenty pounds. Dyers in Lon¬ 
don are fubjecl to the infpetlion of the dyers company, 
who may appoint fearchers ; and out of their limits, juf- 
tices of the peace in feftions to appoint them: oppofing 
the fearchers, incurs ten pounds penalty. 
DYKE-REED, rather Dyke-Reeve,/! An officer that 
hath the care and overfight of the d)kes and drains in 
fenny countries; as of deeping-fens, &c. 16 & 17 Car. II. 
c, 11. 
DYLF,, a river of the Netherlands, which rifes on the 
north-weft of Namur, and joins the Scheld above Niel, 
after receiving front the eali the waters of the Dermer, 
the Nette or Nethe from the north, and the Senne from 
the loath. 
DY'MAS, a Trojan, who joined himfelf to cEneas 
when Troy was taken, and was unfortunately killed by 
his countrymen, w ho took .hint to be an enemy, becaufe 
he had drefled l.imfelf in the armour of one of the Greeks 
he had (lain. Virgil. 
DY'NAMIS,^. [from Siita-peu, Gr. to be able.] With 
phyficians, tlie power by which any medicine operates, 
or front'whence any atftion proceeds. 
DYNA'MICS.y^ \dynamique , Fr. of Swapii;, Gr. power, 
force, cYc. ] That department of mechanics which relates 
to the motion of bodies ; as ftatics relates to the equili¬ 
brium of bodies, or where no motion is produced : the 
two grand divisions of mechanics being Jlatics and dyna~ 
mics ; the former relating to quiefcence, and the latter to 
moving forces. See the article Mechanics. 
DYNANO'METER, J. an ingenious inftrument for 
afeertaining the relative ftrength of men and animals.—> 
When Sanftorius invented hjis balance, he taught us 
what we lofe by infenfible perfpiration; and no one, 
without this difcovery, would perhaps ever have ima¬ 
gined that the matter thrown out from the body is more 
than half what we receive as nourifhment. Knowledge 
no lefs important might be acquired, had we the eafy 
means of afeertaining, in a comparative manner, our re¬ 
lative ftrengths at the different periods of life, and in 
different dates of health. With this view a dynanome- 
ter was firft invented by Graham, and improved by 
Dr. Defaguliers, at London; but this machine, conftruft- 
ed of wood, was too bulky and heavy to be portable ; 
and, belides, to make experiments on the different parts 
of the body, feveral machines were necelfary, each fuited 
to the part required to be tried. The next improvement 
was the dynanometer of Cit. Leroy of the academy of 
fciences at Paris. It confided of a metal tube, ten or 
twelve inches in length, placed vertically on a foot like 
that of a candleftick, and containing in the infidea fpiral 
fpring, having above it a graduated (hank terminating in 
a globe. This (hank, together with the fpring, funk into 
the tube in proportion to the weight adding upon it, and 
thus pointed out, in degrees, the ltrength of the perfon. 
who preffed one the ball with his hand. 
X x 
This 
