COLOURS. 81 



smallest loss of weight ; and if a leaf of woodruff (as- 

 perula odorata) be worn for some time in the case of 

 a watch, the watch will retain the scent for years, even 

 though it has been again and again brushed and cleaned 

 by the watchmaker. There is a something, too, that guides 

 the vulture to its prey, the bee outwards to the honied 

 nectary and homewards to the nest, and the insect 

 to the proper nidus for its young, although for itself, 

 personally, that nidus has no attraction. The common 

 process of the dispersion of the substance in the same 

 way that water is evaporated, or the moisture of a 

 pulled leaf dried up by the sun, will not account for 

 these changes. In the case of the insects, it cannot 

 be a sense of smell, in our meaning of the term ; be- 

 cause that would be as acute to danger as to pleasure ; 

 and we have placed a little basin with chips of wood 

 and sulphur in a state of ignition, where bees were 

 busy around, and unless they came into absolute 

 contact with the fumes, not a bee of them was 

 disturbed ; yet those same bees found their way to 

 the honey in the nectary of a scentless flower. 



The colouring, too, the motion, and the life itself, 

 though in so far dependent upon light and heat, must 

 depend upon other action. So far from colours being 

 the more brilliant, the more they are exposed to the 

 sun, the direct sun blanches the red rose; and the 

 fanciers of auriculas, tulips, and other gaily coloured 

 flowers, carefully shade them from the solar action. It 

 is true that the colours are in the light, because it can 

 be decomposed into them, and without light there is no 

 colour at all ; but still the tints appear not without de- 

 composition, and the hues of the flowers are even more 



