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EXHIBITION OF 1881-OPENING ADDRESS. 
Notwithstanding, then.9- the small amount of nitrogen in 
the cereals, they are among those plants most benefited by 
nitrogenous manures. Now the clovers and all the legu- 
minous plants possess the property of containing a great 
amount of nitrogen; at least twice as much as do the cereals; 
the amount of potash and lime in these plants is also very 
great. The oxygen in the atmosphere, oxydizing these leg- 
uminous plants, both root and su'rface growths, changes the 
nitrogen into nitric aeid, which again, uniting with bases 
in the soil, forms nitrates, which are readily soluble, and 
are the direct food of'the cereals. In land which has ordi- 
nary fertility resulting from reasonable application of barn- 
yard manures, the supply of plant-food is large, and a. 
luxuriant growth may usually be obtained by supplementing- 
the elements usually found in the soil by a few speeifie ele- 
ments in small quantities for partieular crops in their order 
of rotation. Thus the cereals may need a special application 
of nitrate of sodium, and superphosphate, and then a full 
crop of either barley, wheat or oats may confidently be ex- 
peeted. In like manner the use of nitrate of sodium alone, 
will produee a full erop of mangels; superphosphate alone,- 
a full crop of turnips, when the season is favorable; ancl po- 
tassiäm salts alone will produee a most benefleial effect on 
pastures and the clovers. It is not the intention of this ad-- 
dress to teach the 
SCIENCE OF, AGRICULTURE. 
My objeet is to present in a brief and simple way, the re- 
lation of seience to practice, and to give a few illustrations 
of this relatioü., hoping that by such means, the majority of 
us may more clearly see the great need of knowledge as the 
ground and promise of prosperity. Let us now occupy our- 
selves for a few min'utes with the subjeet.of under-draining 
The first and most direct effeet is the removal of surplus 
water from the soil. The presence of this water in wet sea- 
sons and especially in heavy soils, is a most serious hindrance 
to the growth of vegetation; with the water line lowered, 
Wou may expeet a full erop, when otherwise you would have 
a very small return. All good influenc-es stop at the water