53 6^ 



fuppofe 



PRODUCTION 



Sect. XIX 



ppens 



that the beds of centaurea cyanus become of 



fuch various and beautiful (hades of blues, purple 



and whites, 

 feedlins: flo 



Another method of giving variety of colours to ^^ ^ 



nfifts in fowing them on natural foils, or on faaitious compofts 



hich differ much from each oth 



m 



refpe6l 



to 



o 



etable nu 



men 



and perhaps in refpe6: to th 



mals change their natural colours when in 



colour, as fome ani- 

 different fituations of 



foil, 

 they 



As -frogs 



mu 



r 



femble th 



colour of the foil on which 



d our domefticated horfes, dogs, cats, rabbits, pigeons 



> 



d poultry, change their colours into en 



dlefs varieties, owing to 



difference of their nutriment or fituation 



But obfervations and 



penmen 



th 



s fubjea in refped to the colours of 

 feedling flowers, as well as in refpe6l to the variegation of the leaves 

 of (hrubs and trees ; which laft originates probably from foil or fitua- 

 tion, and may be propagated by ingrafting. 



As the origin of double flowers is believed to refult from the lux- 

 uriant growth of the plant, owing to too much nourifhment, 

 ture, and warmth, fo the origin of new colours in flowers, 



moif- 

 md of 



^ated fol 



& 



foil 



ffht to occur from the innutrition of th 



ive na 



hich they grow, corripared to that which they h 



rally been accuftomed 



or from defeat of moiflure and of heat 



wh 



th 



r 



which is countenanced by the dwarfifli fize of fuch pi 

 and efpecially by the leffened ftature of tulips, 



.break into variety of colours. 



The proximate caufe of the change of colours in flowers or foliag( 



muft be fought from the modern acquifitions of aerial chemiftry 

 The prefence of oxygen gas deprives dead vegetable fibres, as cotton 



Avool and the threads of fl 



of 



colour ; that is, it bleach 



them ; 'which is probably owing to its uniting with the colouring 



matter and forming 



a new acid, which is tranfp 



Th 



th 



hyper-oxygenated muriatic acid almofl inflantaneouily dep 



^nd linen of th 



colour; and the fun's light on moiftencd 



linen 



/ 



