PLATE XVIII. 
The credit of this invention is claimed by the French ; and it is 
said they have arrived at such a degree of perfection in the art, that 
independant of the plain silvery hue of the beads in common, they 
can vary the colour to blue, green, or any other vivid tint they may 
desire. The process is very short ; the scales are scraped off, washed, 
and then reduced to a fine powder ; this is diluted with water, and 
introduced into a thin bubble of glass, where it forms an internal 
coating : the cavity is then filled with wax, through which a hole 
is bored, and the bead is finished. 
Gmelin speaks of this species as being from four to ten inches 
in length : in the river Thames, about Battersea, or still higher up 
the country, they are sometimes taken full eight inches in length ; 
but the common size scarcely exceeds five or six inches at most. 
At certain times in the summer, the Bleak is infested with a 
creature of the Vermes tribe, which hastily increasing in size, very 
often destroys it. Fishes so infested rise to the surface of the water, 
where they leap and tumble about in the greatest agonies, and in 
that state are well known to the fishermen by the name of Mad 
Bleaks. Upon opening them at this season, there is always found 
one, and sometimes more of these worms, in the intestines of each : 
these rapacious creatures are flatfish, broad, and when extended, are 
oftentimes twice the length of the fish they infest. 
The Bleak may be taken at any season of the vear with a hook 
and line. It is distinguished from every other species of the 
Cyprinus genus by the superior length of the under jaw. The time 
of spawning is in May, June, and July. 
