Comparative Effects of dfferent Manures on Grass Lands. 639 
Mcclinrj of WecUi/ Council, Wednesdaij, June 2ith. The Earl of 
Powis in the Chair. 
The Compakative Effects of diffehent Mancres on Grass Lands. 
Professor Yoelcker (having placed on the table specimens of 
grasses collected by himself on the previous day on Messrs. Lawcs 
and Gilbert's experimental plots at ilothamsted, to which he frequently 
alluded in the course of his lecture), said : My Lord and Gentlemen : 
That grass land is capable of improvement as much as arable land, I 
think few pcojde will deny ; that there is pasture land which is more 
ditiicult to improve than other pastiu'c land, I believe- most people 
will admit ; and that, taking a wide view of the pastures of England, 
there is much grass land in very bad condition, which is capable of 
extensive improvement, I likewise think very few persons \\"ill ques- 
tion. The qiicstion then arises. How is gi-ass land to be improved ? 
— by what means, whether mechanical or chemical, can we increase 
our herbage, both as regards quality and quantity ? 
Before proceeding fui-ther, it may, perhaps, be well to look briefly 
at the question, ^Yhat is to be considered bad and what good 
pastm-e "? To which it will be no sufficient answer to say that good 
pastui'C is land which gives us good herbage and an abundant crop 
of hay. Pasture, then, or grass land in general, may be bad for 
three reasons. First, the soil may be good enough, but imfortunately 
there may be too little of it. Secondly, the physical textme of the 
laud may be bad ; there may be plenty of materials, but the grass 
may rest on a stiff, impervious clay soil 3 feet deep, or on a sub- 
soil which cannot be readily di-ained, in which cases the herbage 
will never be very abundant, and will often come imperfectly to 
matuj-ity. Thirdly, the soil may be bad, because something or other 
is defective in the land, — some ingi-edient wanting which is necessary 
to the luxuriant gi-o^^-th and full development of the plants. It is 
evident that, according to the natui-e of the defect in the soil, we must 
order om- plans of improvement. If pasture is bad or indifferent on 
account of any mechanical or physical deficiency, it is vain to apply 
to it manuring constituents, v.hich, however useful they may be on 
land which is porous and well drained, though naturally poor, produce 
little or no effect on undi-ained cold clays. On pastui-e land, how- 
ever, which has been di-ained and otherwise deprived of its super- 
abundant moistui-e, manuring is, no doubt, one of the most important 
means of improvement. 
The proper selection of fertilizers for gi-ass land cannot be well 
understood, if we disregard the special effect which certain manm-ing 
constituents, such as nitrogen, or mineral matters — phosphatic manm-es, 
alkalies, or lime, produce on the quality as well as the quantity oi 
the herbage. I do not know of any series of experiments calculated 
to bring more forcibly before an observer's view the remarkable 
effects which such manures produce on certain grasses than the very 
carefully conducted experiments at Eothamsted. These experiments 
have been carried on now for a scries of years with an amount 
VOL. XXIV. 2 T 
