43© Dyeing. 



where it never had been fo clearly marked out. The lumi- 

 nous diflc difappeared laft. 



** Thefe obfervations were made by a great number of 

 people, as it was market day in the place. As prejudice* 

 are ftill very ftrong in mod parts of the country, every one 

 reafoned according to his religious or political prejudices — ■ 

 Some faid that it was a fign of the anger of God againft the 

 changes which had taken place : others, of an oppofite opi- 

 nion, faid that God had crowned the republic : others again 

 thought that the great circle which feemed to embrace all 

 this hemifphere, announced a general peace." The writer of 

 the account concludes, " I had no great difficulty in per- 

 fuading the majority that thefe figns were the effect of the 

 vapours and exhalations occafioned by the heat. Ten yeart 

 ago I mould not have been fo fuccefsful." 



DYEING. 



Cit. Chaptal, having been lately engaged in examining the 

 caufes of the fixity of certain yellow colours, has obferved,. 

 that the yellow colour extracted from vegetables is in general 

 in the inverfe ratio of its fplendour. He has endeavoured to 

 afcertain the caufe which renders the pale yellow more du- 

 rable, and has difcovered it in the exiftence of the tanning 

 principle, which is found united with the yellow principle 

 in moil vegetables. By analyfing fuftic (morus lindoria) he 

 obtained, ift, a principle partaking of the nature of refin» 

 or gums, and which can communicate a beautiful yellow 

 colour ; 2d, an extractive principle, which is alfo yellow, 

 and furnifhes a beautiful colour ; 3d, a tanning principle, of 

 a pale yellow colour, which grows black in the air and by 

 ebullition — it tarnifhes the colour of the other two princi- 

 ples. As it was necefTary to feparate the tanning principle, 

 in order to leave to the reft the full vivacity of their colour, 

 Chaptal found means to accomplifh that object by a fimple 

 and cheap procefs. He boiled, with the wood, fome animal 



fubftance 



