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of which I have the honour to be chairman, I lately learned 

 some things that surprised me. When speaking just now of 

 the Yorkshire College, I alluded to a circumstance mentioned 

 in the report that some of the students there had made several 

 of the coal tar colours from benzol. That statement does not 

 convey much significance to the uninitiated without explanation. 

 Benzol itself, as I understand, is an extract from common coal 

 tar. What are known in the trade as the aniline colours were 

 the first dyes produced from coal tar ; but it was found by ex- 

 perience that while these suited very well for silk or woollen 

 fabrics, as they became fast without a mordant, they did not 

 answer for goods made from hard fibres, like flax and hemp. 

 The first aniline colour of commerce was mauve. This was 

 an entirely new colour ; and I well remember the sensation 

 that its appearance created three or four-and-twenty years ago. 

 A German chemist, Hoffman, then brought out other colours, 

 rosaniline, magenta, &c. Another extract from benzol is an- 

 thracine, and from it are derived all the so-called alizarine 

 colours. The colour basis of alizarine is scarlet : it is largely 

 taking the place of madder, which was hitherto the principal 

 red dye, yielding derivatives of purples and down to chocolate 

 colours. From the alizarine scarlet as a basis the derivatives of 

 purples, lilacs, &c, can also be obtained. A German chemical 

 company have lately brought out an alizarine blue which seems 

 likely to supplant indigo, the latter being not only more ex- 

 pensive, but also more difficult to work. Again, we have ali- 

 zarine orange, and a variety of graduated shades derived from 

 it, down to brown. Other products from the same original 

 base — coal tar — are ceruline, which produces a green, and 

 mytheline green, from which also a blue can be derived. I 

 shall go no further into details, but the examples given will 

 suffice to show the variety and perfection of these new colours, 

 and the reason I mention the matter at all is partly to illustrate 

 the progress of chemical research in this particular direction, 

 and its use to commerce, and partly to state that these colours, 

 used so largely in our dye and print works, are all made in 

 Germany. We in our gasworks make the coal tar from which 



