108 G7/2)Sum as a Manure to Artificial Grasses. 



the spontaneous decomposition of them all. The housewives 

 consider hard water^ which commonly owes its properties to the 

 presence of this salt, to be rather a greater sweetener of tainted 

 food than soft water. Davy, also, in some experiments with 

 minced veal, thought that the addition of the gypsum rather re- 

 tarded putrefaction. 



There is no reason to believe but that the proportion of sul- 

 phate of lime, found in certain plants, is as essential to their 

 growth as the presence of the other earthy salts and pure earths. 

 Thus, those plants which yield this salt never grow well on lands 

 which do not contain it : those in which carbonate of lime is 

 found never flourish in soils from which this salt is absent. 

 Plants which abound with nitrate of potash (saltpetre), such as 

 the sun-flower and the nettle, always languish in soils free from 

 that salt; but when watered with a weak solution of it, their 

 growth is very materially promoted ; and the saltpetre is then 

 found, as shown upon analysis, in very sensible proportions. The 

 same remarks apply to the growth of those plants which contain 

 common salt, or phosphate of lime ; the effect is the same, the 

 result invariable. 



I have noticed, in applying gypsum to grasses, that the weather 

 at the time of spreading it has a very material influence upon the 

 result of the experiment. Its effects are never soon apparent 

 when it is sown in dry weather ; but if the season is damp, so that 

 the white powdered gypsum adheres to the leaves and stalks of the 

 young grass, the good effect is then immediate. This observation 

 was made, many years since, by Arthur Young, by Mr. Smith, 

 and by the American farmers : it is a well-known fact with the 

 saintfoin growers, of the Berkshire and Hampshire chalk forma- 

 tion ; the clover cultivators of the gravels and loams of Surrey 

 and Kent; and on the lucern grounds of the alluvial soils of 

 Essex and Middlesex. The farmers of the United States, when 

 dressing their turnips with gypsum, always found it answer best 

 when spread in rainy weather. 



The result of the analysis of the clover and sainfoin grasses 

 shows that an ordinary crop of these usually contains from 

 1 J cwt. to 2 cwt. per acre of sulphate of lime : now this is pre- 

 cisely the proportion of gypsum which the best cultivators find to 

 be attended with the maximum benefit : those of Kent and Hamp- 

 shire find it useless to apply more ; but then they all agree that 

 the annual repetition of the dressing, as long as the grass is suf- 

 fered to remain on the ground, is attended with renewed benefit. 

 It is here again that the experiments of the chemist and the 

 farmer mutually confirm, and illustrate each other ; the very 

 quantity of sulphate of lime which the first shows to be carried 

 off the land in the clover, is precisely that which the latter returns 

 to it in his dressings with gypsum. 



