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that before the season had too far advanced one other division might have been effected, when the number might have been at least quadrupled. The five hundred plants proved extremely vigorous, much more so than wheat under ordinary culture, so that the number of ears submitted to the sickle was 21,109, or more than forty to each of the divided plants : in some instances there were one hundred ears upon one plant. The ears were remarkably fine, some being six or seven inches long, and containing from sixty to seventy grains. The wheat, when separated from the straw, weighed forty-seven pounds and seven ounces, and measured three pecks and three quarters, the estimated number of grains being 576,840.
Such an enormous increase is not of course attainable on any great scale, or by the common modes of culture; but the experiment is of use as showing the vast power of increase with which the most valuable of vegetables is endowed, and which, by judiciously varying the mode of tillage, may possibly in time be brought into beneficial action.
The ordinary produce of wheat varies exceedingly, depending much upon the quality of the soil, the nature of the season, and the mode of culture. The average produce of the soil of a country depends, as does every other species of production, upon the advance of its inhabitants in knowledge and in the possession of capital. It has been conjectured, that in the 13th century, an acre of good land in England would produce twelve bushels of wheat *. In two centuries this rate of produce appears to have greatly increased. Harrison, writing in 1574, says, " The yield of our corne-ground is much after this rate following :-Throughout the land (if you please to
Sir J. Cullum's "History of Hawksted,' quoted in Eden's · History of the Poor,' vol. i.p. 18.
make an estimate thereof by the acre), in meane and indifferent years, wherein each acre of rie or wheat, well tilled and dressed, will yield commonlie sixteene or twentie bushels; an acre of barley, six-and-thirtie bushels ; of otes, and such like, four or five quarters; which proportion is notwithstanding oft abated toward the north, as it is oftentimes surmounted in the south*.” The mean produce in Great Britain, according to the estimate of Mr. Arthur Young, did not, at the time when he wrote (about 50 years ago), exceed twenty-two and a half bushels
per Other and later writers have calculated the average at from twenty-four to twenty-eight bushels; while the author of the Reports on Agriculture for Middlesex has asserted, that the medium quantity in that county is forty bushels, the highest produce he has known being sixty-eight, and the lowest twelve bushels per acre.
The land in the county which was the subject of these Reports, owing to its proximity to the metropolis, may be considered as in a state of high condition, and much beyond the ordinary rate of fertility. At all times, and in every country, some situations will be found more prolific than others, and some individuals will be more successful in their agricultural labours. Pliny has related a case which occurred among the Romans, where this success was seen in so marked a degree, that the able agriculturist who, by excelling his countrymen, had rendered himself the object of envy, was cited before the Curule Edile and an assembly of the people, to answer to a charge of sorcery, founded on his reaping much larger crops from his very small spot of ground than his neighbours did from their extensive fields. “ In answer to this chargé Cresinus produced his efficient implements of hushandry, his well-fed oxen, and a hale young woman
* • Description of Britain,' prefixed to Hollingshed.
his daughter, and pointing to them, exclaimed,
These, Romans, are my instruments of witchcraft, but I cannot here show you my labours, sweats, and anxious cares.' *»
It will easily be conceived that the quantity of straw must vary considerably from year to year, according to the seasons, and that this produce will likewise be generally influenced by the nature of the soil. It is therefore impossible to give any certain information upon this point, but it will perhaps amount to a near approximation to the truth if we consider that for every twelve bushels of wheat, one load, containing thirty-six trusses of straw, will be obtained, the weight of which is 11 cwt. 2 qrs. 8 lbs. The straw of summer wheat is more agreeable to cattle than that produced from winter sowing:
This most important vegetable is not wholly free from casualties apart from climate. The principal of these are, blight, mildew, and smut. The examination and treatment of these diseases have proved fruitful topics with writers on agricultural subjects. It does not, however, appear that the public has hitherto benefited much by their speculations, and an author of considerable eminence is so far of a contrary opinion as to have asserted, that“ in proportion as words have been multiplied upon the subject, the difficulties attending its elucidation have increased t."
Blight is a disorder to which the cereal grains are known to have been liable from the earliest times, Among the ancient Greeks it was regarded as a sign of wrath on the part of their offended deities; and whenever it occurred they consequently gave themselves up to the infliction, without any thought of providing a remedy. The same superstitious notion was entertained by the Romans, who believed that
* Nat. Hist., book xviii. chap. 6. + Loudon's Encyclopædia of Gardening, p. 236.
the evil, which they called rubigo, was under the control of a particular deity named Rubigus, to propitiate whom in favour of their crops sacrifices were continually offered.
Blight and mildew have been very much confounded together by different writers on agricultural subjects, so as to render it doubtful to which class of appearances each name should in strictness be applied, or whether indeed both are not applicable to one and the same disorder occurring at different periods of the growth of the plant. Wishing to avoid entering upon debateable ground in noticing a subject which remains intricate and obscure, notwithstanding all the laborious treatises to which it has given rise, the forms which the disorders assume, and the bad effects by which they are followed will be plainly but briefly described, leaving the question of their classification to more professional hands.
Three distinct and dissimilar causes are assigned for the production of these disorders-cold and frosty winds-sultry and pestilential vapours--and the propagation of a parasitical fungus. The first of these causes acts by stopping the current of the juices; the leaves, being then deprived of a necessary portion of nutriment, speedily wither and die, when the juices, which are impeded in their passage, swell and burst the vessels, becoming then the food of myriads of little insects. These make their appearance so suddenly as to have been considered the cause rather than one of the effects of the disease. The second cause of blight occurs after the grain has attained its full growth. It has been observed to happen mostly after heavy showers of rain, which, occurring about noontide, have been succeeded by clear sunshine. The plants are most commonly attacked thus about the middle or end of July. Mr. Loudon informs us that “in the summer of 1909, a
field of wheat on rather a light and sandy soil came up with every appearance of health, and also into. ear, with a fair prospect of ripening well. About the beginning of July it was considered as exceeding anything expected from such a soil. A week afterwards, a portion of the crop on the east side of the field, to the extent of several acres, was totally destroyed, being shrunk and shrivelled up to less than one half the size of what it had formerly been, and so withered and blasted as not to appear to belong to the same field. The rest of the field produced a
This disorder attacks either the leaves or stem of the plant, which appear to be covered by broken lines, of a black or deep brown colour. This disease has been ascertained to result from the
presence of a very minute species of fungus, the roots of which are inserted into the stem, and absorb the nourishment intended for the grain, which when the plant is thus attacked proves little else than husk. The minute seeds of the parasitical plant which occasion this mischief are so exceedingly light that they are borne along by the air to considerable distances. They are likewise of extraordinary quick growth, occupying in warm weather, according to the opinion of Sir Joseph Banks, not longer than one week from the time of their insertion in the plant to the production of their seed. Every pore in the straw whereon they fix will present from twenty to forty plants, so that the extent to which this mischief spreads is difficult to be imagined. Fungus thrives best in damp and shady situations, a circumstance which seems to point out naturally the propriety of providing means for the free ventilation of the fields, keeping low the hedges and fences by which they are surrounded. For the same reason it is found that thin crops, and
* Encyclop, of Gard. p. 237,