" 798,267
Eggs 373,042,000

I am indebted to Professor Ferguson, Chief of the Veterinary Department
of the Irish Privy Council Office, for the following statement:--

RETURN OF HORNED CATTLE EXPORTED FROM THE SEVERAL IRISH
PORTS AT WHICH VETERINARY INSPECTORS HAVE BEEN APPOINTED,
AND CERTIFIED AS FREE FROM DISEASE, FROM THE 18th OF
NOVEMBER, 1866, TO THE 16th OF NOVEMBER, 1867 (52 WEEKS).

Fat Stock 187,483
Store Stock 317,331
Breeding and Dairy Stock 36,599
--------
Total 541,413
========

PART I.

ON THE GROWTH AND COMPOSITION OF ANIMALS.

SECTION I.

ANIMAL AND VEGETABLE LIFE.

_Functions of Plants._--It is the primary function of plants to convert
the inorganic matter of the soil and air into organised structures
of a highly complex nature. The food of plants is purely mineral, and
consists chiefly of water, carbonic acid, and ammonia. Water is composed
of the elements oxygen and hydrogen; carbonic acid is a compound of
oxygen and carbon; and ammonia is formed of hydrogen and nitrogen. These
four substances are termed the _organic elements_, because they form by
far the larger portion--sometimes the whole--of organic bodies. The
combustible portion of plants and animals is composed of the organic
elements; the incombustible part is made up of potassium, sodium, and
the various other elements enumerated in another page. The organic
elements are furnished chiefly by the atmosphere, and the incombustible
matters are supplied by the soil.

Water in the state of vapor forms, according to the temperature and
other conditions of the atmosphere, from a half per cent. to four and a
half per cent. of the weight of that fluid--about 1.25 per cent. being
the average; carbonic acid exists in it to the extent of 1/2000th; and
ammonia forms a minute portion of it--according to Dr. Angus Smith, one
grain weight in 412.42 cubic feet of air (of a town), or 0.000453 per
cent. It is remarkable that the most abundant constituents of atmospheric
air--oxygen and nitrogen--are not assimilable by plants, although these
elements enter larg