218 ON RAISING ROSES FROM SEED. 



light in the coloration of plants. He caused young colourless plants 

 to grow in different glass vessels, so constructed that the light which 

 fell upon them should first pass through fluids of different colours, 

 red, yellow, and violet. At the end of four or five weeks the leaves 

 which had been exposed to red light had a tinge of green ; those in 

 the yellow light were at first green, but afterwards became yellow ; 

 and those in violet light were quite green, and the depth of colour 

 increased with their age. (Mem. Phys. Chim., torn. ii. p. 55, etseq.) 

 The subsequent experiments of Ritter and Wollaston have shown 

 that these effects were produced, not by the coloured rays, but by 

 certain invisible rays associated with them, and which exist in 

 greatest force at and beyond the boundary of the violet extremity of 

 the spectrum. To these rays have been assigned the names of the 

 chemical or deoxidating rays ; of their deoxidating power we shall 

 have abundant evidence in the next section. 



( To be continued.) 



ARTICLE V. 



ON RAISING ROSES FROM SEED. 



BY ROSA. 



In recent Numbers of the Floricultural Cabinet I have with 

 pleasure noticed the observations on hybridizing various plants, with 

 a view to the increased improvements of the various genera of orna- 

 mental plants. I have for several years directed my attention to 

 raising Roses from seed, and my efforts have been successful in 

 raising some of the finest new Roses which now grace our best col- 

 lections. 



During the months of September and October I repaired to several 

 first-rate nursery collections of Roses, in order to see which kinds, in 

 each class of Roses, bore fruit the most freely, and ripened the ear- 

 liest ; and I then procured several of each class, which I planted at 

 the proper season. These bloomed the following summer, and having 

 a very extensive collection of nearly all the finest double Roses, I 

 carefully selected farina from the best of the double flowers, and im- 

 pregnated the fruit-bearing kinds therewith. The fruit-bearing 

 flowers are generally not quite double, and I found it to be of use to 



