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prooting, and ornamenting fabrics by means of flocks of 
different colours by Henry Johnson, in 1797; the use of high- 
pressure steam for the purpose of bleaching by Turnbull, 
in 1800; and the more perfect mode invented by Wright, 
in 1825; James Thomson’s celebrated process for discharging 
the colour from Turkey red cloth by means of an acid and 
a solution of chloride of lime, in 1813, and his still more 
celebrated invention of printing metallic solutions on dyed 
fabrics, and immersing them in a solution of bleaching 
powder; Joshua Rowe’s discovery, in 1818, of the formation 
of sulphate of alumina by the direct action of sulphuric acid 
upon clay, aided by a dull red heat ; B. Woodcroft’s process 
for printing deoxidized indigo ; Mercer, Prince, and Blythe’s 
introduction of the arseniates and phosphates as substitutes 
for dung ; Steiner’s process for making garancine from spent 
madder ; Mercer, Greenw’ood, and Barnes’s invention of dry 
stannates; Mercer and Greenwood’s important improvement 
in the art of dyeing Turkey red, on June 22, 1846 ; 
Broguette’s process for fixing colours by means of nitro- 
genous substances aided by steam, in some degree anticipated 
by Thomas Preston, in 1773; and Mercer and Blythe’s 
introduction of the double salt of arseniate and stannate of 
soda as a preparation for fabrics. 
PHYSICAL AND MATHEMATICAL SECTION. 
March 1st, 1860. 
Mr. Lowe read a Paper “ On a Compound Compensated 
Pendulum of Steel and Zinc.” 
A short account was first given of one made at the sugges- 
tion of the late Rev. H. H. Jones. The rod of this pendulum 
was of wood, and the bob rested upon a zinc tube which 
stood upon the regulating nut at the end of the rod. 
