18-2 
kerne, and Womersley, in the paper read by me at Wake- 
field, and I fear that this operation is not duly appreciated, 
and wish, therefore, to add the following quotation, taken 
from the History of the State of Improvement in Scotland, 
since the end of the 17 th century. After speaking of the 
establishment of the Highland Society, and the introduction 
into Scotland of the turnip husbandry, the author says, 
" There yet remains another epoch in the history of Scotch 
" agriculture to be spoken of — the thorough or Deanstone 
" mode of draining. This so great benefit, not for Scotland 
" only, but for the whole kingdom, is yet in its infancy. 
" Already the fame of the utility of it is spreading all over 
" the island, and we have no doubt, in a short time, there 
will not be found a spot (where improvements are carried 
" on,) that has not been made anew by means of this simple, 
" yet powerful and efficient system of draining. Now no 
" man holding land ought to be ignorant of the thorough or 
Deanstone drain. It is perfectly wonderful to behold the 
mighty change this thorough drain system is making in 
" different parts of the country where it is in operation; 
" wet land is made dry, poor weeping clays are converted 
*' into turnip soil, and even what would formerly have been 
" accounted dry is advanced in quality. Whole parishes in 
" the vicinity of Stirling are transformed from unsightly 
** marshes into beautiful and rich wheat fields, and where 
the plough could scarcely be driven for mud and water, we 
" see heavy crops per acre." 
There is one word to be said concerning the use of gyp- 
sum, which abounds in the bed of red marl; the places 
where it has been dug have been mentioned. The chemical 
properties of gypsum, as a manure, are not well understood '; 
its operation is to fix the ammonia which exists in the air, 
and in the richer manures in the soil. The gypsum is de- 
composed by the carbonate of ammonia, and the result is 
