22 INTRODUCTION. 



The rimniDg of fine double flowers, that is> 

 suddenly returning to their whole or original 

 colour, has long been the plague and puzzle of 

 florists. They have never been able to account 

 for the circumstance satisfactorily. Some ima- 

 gine that the change is caused by too much or 

 too rich dress ; others assert that an over-lean 

 or sandy soil produces the same effect ; and it 

 appears clearly proved, that in very dry and 

 warm summers such mutations of colour take 

 place, even more extensively than in ordinary 

 seasons. 



As relating to this circumstance, may be men- 

 tioned a very general opinion amongst the culti- 

 vators of flowers, that the richer the soil the 

 deeper will be the tints of the bloom. The co- 

 lour of the hydrangea hortensis can be changed 

 by the qualities of the mould in which it is 

 placed ; and the natural colour of the common 

 primrose is very soon changed to a pink or yel- 

 lowish brown by being planted in cow-dung. 

 On this account it is, that the pure droppings of 

 animals have always been preferred as a princi- 



