A Discovery in Brick-Making.

Taranaki Daily News, Volume XXXV, Issue 255, 26 November 1903, Page 4

A Discovery in BrickMaking.

vv n. Acheson, of Niagara Tails a .1.. claims to have discovered why the Egyptian use< i SUaw in t] J manufacture of their bricks According to Mr Aclieson, it was Lot alono as a binding material, but because the tannin extracted bv the soaking of the straw in water* added greatly to the strength of the IVicks. By treating clav with on oxtract of straw, Mr Acheson has shown a. 50 per ctmt. increase in tensile strength, and an increase of plasticity, with a ■decrease of shrinkage. The clay is worked with water in which straw has been boiUi. So little as one-half 1 per cent. of tannin is said to develop a wonderful effect, the clay rehiring 13 per cent. less water to make it soft. The maximum effect of the process and treatment, however, seems to be obtained by the use of 2 per cent, cf tannin in a 10-day treatment. The treutincnt is merely keeping the clay wet with water in which the tannin is ■dissolved, which can be done in vats. Besides the abovementioned .50 per cent, increase of strength in the burnt form, the clay in the •un-hried form acquires an increase of 350 per cent, in tensile strength. As a result of this discovery Mr Acheson has patented a combination of clay and tannin under the name of "Egyptianised clay." Canadian Architect and Builder.