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DYEING AND CALICO PRINTING.

The most important modifications of the continuous process of bleachingrecently are those patented by Mr. Barlow in 1866. This inventor combinesin one machine not only the various apparatus required for bleaching, but theoperations successively of dyeing, printing, and sizing, subdividing the troughsor cisterns containing the mordants and the dyes by cross partitions, so that the

Fig. 6.

several threads passing through the machine at the same time may be dyedin different colours or partly left uncoloured.

These machines are, however, not adapted to the bleaching of linen.Linen does not possess the elasticity of cotton, and the strain would eitherpull the cloth narrow or tear it.

Bleaching with other Chemical Agents.

Several processes of bleaching with the aid of chlorochromic acid, chromates,chlorates, manganates, and sulphites have been from time to time introduced,but the operations have not been sufficiently successful or the use soextensive as to call for detailed description.