170 ON PLANTING AND MANAGING 



the whole vinous latitude. In no part of the world can 

 a vine be made to produce a single grape more than it 

 otherwise would do, by the exclusive agency of any 

 thing added to the soil in the shape of a stimulant, ex- 

 cept under the circumstances hereafter mentioned. 

 Grapes are the sole creation of solar light and heat. 

 The earth produces the raw material in the form of 

 branches and leaves, but the sun must step in and con- 

 solidate the juices, otherwise not a single grape will be 

 produced. 



Here, then, is the grand distinction to be made in 

 the effect produced by manuring the roots of vines, ac- 

 cording to the latitude in which they grow. 



Assuming that in all the countries where the vine is 

 indigenous, and which in the northern hemisphere are 

 generally considered to be comprehended betwixt the 

 25th and 44th degrees of latitude, the two powers of 

 the vine are, as has been already stated (for a little re- 

 petition is necessary here for the sake of clearness), 

 equally balanced, that is, that every vine is sufficiently 

 strong in its growth to perfect all the grapes it pro- 

 duces; then in all these countries stimulants to the 

 soil may be added to advantage, because any increase 

 in the shoots of a vine there will be followed by a cor- 

 responding increase in the quantity of fruit. 



Passing, however, the southern limit of this district 

 towards the tropic, the light and heat of the sun be- 

 comes too intense for the vine, the shoots and leaves 

 of which are exhausted by excessive perspiration, and 

 cannot, therefore, yield that nourishment which the 

 maturative powers of the plant require. 



In countries, therefore, where this is the case, man- 

 ure may be added to the soil with even greater advan- 

 tage than in the native district of the vine. But as 

 soon as we pass northward of that specific line of de- 

 marcation which terminates the northern limit of the 



