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and Dyeing Turkey Med . 
For dyeing my red, I employed three parts of the best 
madder for one part in weight of dry cotton thread. 
With the precaution I took to obtain an uniform shade 
I could have dyed at one time, but I should always re- 
commend performing this operation at two different times, 
taking each time half a portion of madder and of chalk, 
if the skains cannot be continually turned in the boiler : 
it may serve also for clearing, by adapting to it a cover 
so as to suffer very little of the vapours to escape, be 
cause it would be too expensive to replace the part eva 
porated by more boiling water. By operating on a large 
scale, and concentrating the heat in the boilers, keeping 
them almost close, there, perhaps, would be no need of 
employing eight hours ebullition to clear and fix the co- 
lours. I have every reason to believe that this clearing 
of the Turkey red gave rise to the idea of bleaching with 
steam : it must have been seen that colours by being 
cleared lose considerably in regard to their intensity ; and 
perhaps it has been observed at the same time that the 
packthreads employed for arranging the skains were 
bleached during the clearing, especially when alkalies 
were added. 
A great variety of colours and of different shades may 
be obtained by following the process here described for 
obtaining beautiful and durable reds. In this case, the 
oily alkaline solution of alumine must not be employed 
till the required shade of oxide of iron or indigo blue 
has been given ; but whatever may be the colour or shade 
which you wish to give, before you fix the alumine on the 
skains of cotton or linen, these skains must always be 
first well boiled, by which means the adhesion of the in- 
digo fecula as well as that of the oxide of iron will be 
increased, in the same manner as that of alumine colour* 
ed by the colouring parts of madder when subjected to 
the action of the heat of boiling water before they are 
