76 E L A 
fmoothed and poliffied, more of the light is refiefted from 
it, and the intenfity'of the blacknefs is diminilhed ; though 
the beauty may be improved by the glofs which refults 
from the fmoothing- There is one cafe, however, in 
which a high polifh may, on the fame principle, produce 
blacknefs, in bodies otherwise even white. We find that 
fpecula of white metal, or of quickfilver glafs, which re¬ 
flect the rays of light to one point or in one direction, look 
always dark, unlels when the eye is diredtly oppofed to 
the reflected rays. 
“ As the abforption of the luminous rays, except in 
the cafe juft mentioned, makes the phyfical caul’e of black- 
nefs ; it is concluded that black bodies receive heat more 
freely than others. Black marble or tiles, expofed to the 
fun, become fenlibly hotter than white ones. Black paper 
is kindled by a burning-glafs much fooner than white, 
and the difference is ftrongly marked : a burning-glafs, 
too w r eak to have any vifible effect at all upon White pa¬ 
per, fhall readily kindle the fame paper rubbed over with 
ink. Hence black cloths when wetted, are laid to dry 
fafter ; black habits, and rooms hung with black, to be 
warmer ; black mould to be a hotter foil for vegetables ; 
and garden walls, painted black, to anfwer better for the 
ripening of wall-fruit than thofe of lighter colours. Dr. 
Watfon, biihop of Landaif, covered the bulb of a ther¬ 
mometer with a black coating of Indian ink, and the con- 
fequence was, that the mercury rofe ten degrees higher. 
A virtuofo of undoubted credit alfo allured Mr. Boyle, 
that in a hot climate, by blacking the fliells of eggs, and 
expofing them to the fun, he had feen them thus well 
roafted in a ftiort time. It is not, however, to be affirmed 
that the like differences obtain in the impreffions made by 
common fire. Black paper, held to the fire, does not feem 
to be afleffed fooner, or in a greater degree, than fuch as 
is white. It may be proper to obferve alfo, that the com- 
buftibility of the paper may be increafed, by impregnating 
it with fubftances of themfelves not combuflible, and 
which give no colour to it. This is the foundation of one 
of the fympathetic inks, made of a flrong folution of fal am¬ 
moniac in water, which, though colourlefs when written 
with on paper, becomes very legible on expofing the pa¬ 
per to the fire ; that is, it occalions the parts moiftened 
with it to fcorch or burn, before the reft of the paper is 
hurt, to a brown or black, 
“ All colours in a very deep or concentrated ftate ap¬ 
proach to blacknefs. Thus the red liquor prepared by 
boiling or infufing madder-root in water, and the yellow 
decoction or infufion of liquorice-root, evaporated in a 
gentle heat till they become thick, look of a black colour, 
or approaching to blacknefs ; and thefe thick maffes, drawn 
out into flender firings, or diluted with water, or rubbed 
on paper, exhibit again the red and yellow colours, which 
the liquors had at firft. Nature affords many black ob¬ 
jects, whofe blacknefs depends upon the fame principle, 
being truly a concentration of fome of the other colours. 
Thus in black-berries, currants, elder-berries, See. what 
feems to be black is no other than an opaque deep red : 
their juice appears black when its furface is looked down 
upon in an opaque veifel, but red when diluted or fpread 
thin. The black flint, as it is called, of the ifland of 
Afcenfion, held in thin pieces between the eye and the 
light, appears greenifn ; and one of the deep black ftones 
called black agate, viewed in the fame manner, difeovers 
its true colour to be a deep red. The black colours de- 
feribed by Dr. Lewis, are as follow : The black chalk of 
the (hops, which feems to confift of an argillaceous earth, 
impregnated with bituminous matter, reduced to the ftate 
of coal. Pit-coal, which affords a brown black, and is 
act eafilv ground to a fufficient finenefs. The black fer¬ 
ruginous lands, which are of little ufe as pigments. Plum¬ 
bago, or black lead, tiled for pencils. Black vegetable 
juices; of which lie enumerates the anacardium of the 
Eaft Indies, the juice of which ftains linen or cotton of a 
reddifh brown colour, that Toon changes to a black, not to 
be difeharged by alkalis; the cafhew nut, which affords 
B L A 
a browniffi durable ftain ; and various fpecics of the toxi¬ 
codendron, or poifon tree, from North America, which 
produces a deep black permanent ftain. The cuttle fifh 
ink, or black fluid contained in a peculiar veifel of that 
animal; but whether this ink is of confiderable value for 
its permanency, he had no opportunity of afeertaining. 
Among the blacks produced by fire, the dodtor found that 
the coals of wood, and of animal fubftances, poffefs vari¬ 
ous properties, according to their nature, or original tex¬ 
ture, when ufed as crayons or as pigments. The foot 
blacks are in general much fofter, and more eafdy unite 
with oils. Several of the metals, fuch as manganefe, 
cobalt, and iron, are of a black colour in certain (fates of 
calcination.' See Ink, Varnish, and Dying. 
“ Every bean has its Black.” This is an excufatory 
proverb for the common failings of mankind, and inti¬ 
mates, that there is no man periedt in all points, wife in 
all refpedts, &c. and is a fatire againft cenforioufnefs; and 
accordingly, Vitiis nemo“Jine nafeitur , fays Horace ; and the 
Greeks fay, Tla xogveaMicrt ov EyIwerSaij and 
the Italians, Ognigrano ha la fua Jemola. 
To BLACK, v. a. To make black; to blacken. 
BLACK aCt, or Waltham Black Act,/. The 
fiat 9 Geo. 1. c. 22, is fo called, having been occafioned 
by fome devaftations committed near Waltham, in Hamp- 
flfire, by perfons in difguife, or with their faces blacked. 
By this aft, perfons hunting armed and difguifed, and 
killing or ftealing deer, or robbing warrens, or ftealing 
fifh out of any river, pond, See. or any perfons unlawfully 
hunting in his majefty’s foreft, or breaking down the head 
of any fifh-pond, or killing, See. of cattle, or cutting down 
trees, or fetting fire to houfe, barn, or wood, or (hooting 
at any perfon, or fending anonymous letters, or letters 
figned with fictitious names, demanding money, &c. or 
refeuing fuch offenders, are guilty of felony without be¬ 
nefit of clergy. This aft is made perpetual by 31 Geo. II. 
c. 42. See alfo fiat. 16 Geo. 111. c. 30, againft deer-fteal- 
ers ; the milder punifhment inflidted by which adt has been 
thought a virtual repeal of the punifhment inflidted by 
the Black Adt above-recited. Leach’s Hawk. P.C. i. c.49. 
BLACK'AMOOR,/. [from black and Moor. ] A man 
by nature of a black complexion ; a negro. 
BLACK-BAY, a bay on the fouth-eaft coaft of Labra¬ 
dor. Lat. 51.30. N. Ion. 56. 20. W. Greenwich. 
BLACK-BEAR ISLANDS LAKE, a lake of North 
America, full of fmall iflands, and about thirty miles 
long, and from five to ten wide. Lat. 55. 40. N. Ion. 105, 
40. W. Greenwich. 
BLACK-BERRY,/ The fruit of the bramble. See 
Rubus. 
Then fad he fung the Children in the Wood ; 
How black-berries they pluck’d in deferts wild, 
And fearlefs at the glittering faulchion fmil’d. Gay. 
BLACK-BIRD,/ in ornithnology. See Turdus. 
BLACK-BOOK of the Exchequer. See Exchequer. 
BLACK-BOOKS,/ A name given to thofe which treat 
of necromancy and magic. The black-book of the Eng- 
lifh monafteries was a detail of the fcandalous enormities 
praftifed in religious houfes, compiled by order of the 
vifitors under Henry VIII. to blacken, and thus haften 
their diftblution. 
BLACK-BROOK, a river of England, which runs into 
the Stour, near Loughborough, in Leicefterfhire. 
BLACK-BROWED, adj. [from black and brow.~\ Hav¬ 
ing black eye-brows ; gloomy ; difmal ; threatening : 
Thus when a black-brow'd gufii begins to rife, 
White foam at firft on the curl’d ocean fries, 
Then roars the main, the billows mount the fkies. Dryd, 
BLACK'BURN (William), aneminent furveyorandar¬ 
chitect born in Southwark, the 20th of December, 1750. 
This architedt became celebrated for ms plans of public 
gaols, or penitential houfes, on the principles fuggefred 
by the philanthropic Mr. Howard, which were to be con- 
firufted 
