58 



the Melon has naturally the advantage also, of power- 

 ful sun heat, and intense light ; and these are two 

 conditions which it is indispensable should be supplied 

 in artificial cultivation, as fully as they can possibly be 

 obtained. It is by means of the moisture of the soil, 

 that the plants are enabled to grow on rapidly and 

 vigorously, because that moisture renders the food 

 contained in the soil, soluble, and therefore available 

 to the roots ; but the elaboration and assimilation of 

 this food depends on the degree of light and heat with 

 which they are supplied : without these conditions, to 

 convert the crude sap, by their united agency, into or- 

 ganic compounds, such as lignin, gum, starch, and 

 sugar, and to induce their deposition, the fruit will 

 indeed be formed it will grow, and perhaps may even 

 tempt the eye ; but unless these chemical and vital 

 changes have taken place in its constituent parts, the 

 eye, as it frequently happens, will have been deceived ; 

 and instead of the palate being gratified by a mature 

 and luscious fruit, it will find nothing but a tasteless 

 mass of pulp. The plants, therefore, cannot, in our 

 latitude, receive too intense a degree of solar heat, or 

 of light. 



The same cause which renders the natural atmo- 

 sphere of the Melon countries elevated in temperature, 

 renders it also comparatively dry ; the sun drinks up 

 the moisture which is deposited near the surface, or 

 which may rise to that position ; and by an exceedingly 

 powerful influence effectually prevents the accumula- 

 tion of moisture about the exposed parts cf the plants. 

 The atmosphere is nevertheless not in an arid state ; 

 the evaporation from a well- moistened soil effectually 

 prevents this from being the case, but the excessive 

 heat also as effectually and continually prevents an 

 undue accumulation of moisture in the atmosphere. 



