1 1 8 Processes for preparing Lake from Madder. 



1804, but lain in a closet. I have buried some others of 

 the last year's growth, with a few carrots and parsnips, in 

 a similar manner to my former experiments, the result of 

 which I shall make known to the society. 



Gaernsey, ^ '^'''''^'l]' ^'^ , 



May 17, 1S04. Your obedient servant, 



J. De Lancey. 

 Charles Taijlor, Esq. 



The above potatoes were examined before a committee 

 of the society on the 30lli of July 1801, and found to be 

 in a state fit for vegetation. 



Charles Taylor, Secretary. 



XVIII. Processes for preparing Lake from Madder. Bij 

 Sir H. C. Englefield, Bart.^ 



1. he want of a durable red colour, which should possess 

 somelhinij; of the depth and transparency of the lake? made 

 from cochineal, first induced me to try whether the madder 

 root, which is well known to furnish a dye less subject to 

 chano"e by exposure to air than any other vegetable colour, 

 except indigo', might not produce something of the colour 

 I wanted. 



Several of the most eminent painters of this country have, 

 for some time, been in the habit of using madder lakes in 

 oil pictures ; but the colours they possessed under this name 

 were either a yellowish red, nearly of tlie hue of brickdust, 

 or a pale pink opake, and without clearness or depth of 

 tint, and quite unfit to be used in water-coloured drawing, 

 which was the principal object of my search. 



Mv firr^t attempts were to repeat the process given by 

 Maro'raf in the memoirs of the Academy of Berlin ; but 

 the colour produced by this mode was of a pale red, and 

 very opake, although the eminent author of the process 

 states the colour he produced to be that of " (e sang eri- 

 flamrne," which probably means a deep blood colour. It 

 may, however be observed, that colours prepared with a 

 basis of alumine will appear much deeper when ground in 

 oil than they do in the lump, the oil rendering the alumine 

 nearly transparent. This advantage is, however, lost in 

 water colours. On examining the residuum of the madder 



* From Transactions of the Society of Arts, &c, 15:04. The society 

 voted iheir gold medal to bir H. C. Englefield for this communication. 



root. 



