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London have promulgated more original discoveries, have developed more of the laws of nature, and have united science with the arts more than all the other philosophical writings in the civilized world! Success cannot be doubted, when the worthy baronet who presides in the councils of this society, rouses the attention of five hundred of his friends by the present of the work before us.

During the last fifty years we have seen the most rapid and incredible improvements in all the different species of domestic cattle but the cultivation of their food, in common with that of man, has not been equally improved, nor has the practicability of augmenting the fecundity of grasses and corn been. sufficiently understood. It cannot, we think, be too earnestly inculcated, that we are yet ignorant of the earth's real fecundity, and of its improveable powers of production: doubtless both the quality and quantity of the best corn, in the most abundant harvest, may yet be augmented ten, nay even a hundred, fold. To a subject then so important as the preservation of the principal necessary of life, we turn with eager expectation.

Botanists' (we are told) have long known that the blight in corn is occasioned by the growth of a minute parasitic fungus or mushroom on the leaves, stems, and glumes of the living plant. Felice Fontana published in the year 1767 an elaborate account of this mischievous weed with microscopic figures, which give a tolerable idea of its form; more modern botanists have given figures both of corn and of grass affected by it, but have not used high magnifying powers in their researches.

It is here said, with extreme inattention to facts, that all the agriculturists, except Mr. Kirby (Transactions of the Linnæan Society), have neglected the discoveries of the botanists, in attempting to account for the cause of this evil. We have seen few modern systems of agriculture in which the microscopic observations of the Italian Fontana‡ are not mentioned; and we, as agriculturists, might retort the charge, by observing that the botanists have overlooked the experiments of Mr. Somerville, who ascribes the origin of this disease to great quantities of little insects, and who also founds his opinion on microscopic observations.

'On this account (the supposed ignorance of Fontana's discovery) it has been deemed expedient to offer to the consideration of farmers, engravings of this destructive plant, made

** Observazioni sopra la Ruggine del Grano.'

Sowerby's English Fungi, Vol. II.'

The French papers announce the death of this philosopher on the 10th of April last.

from the drawings of the accurate and ingenious Mr. Bauer, botanical painter to his majesty, accompanied with his explanation, from whence it is presumed an attentive reader will be able to form a correct idea of the facts intended to be represented, and a just opinion whether or not they are, as is presumed to be the case, correct and satisfactory.'

Of these facts,' or rather opinions, we shall endeavour to give an idea, without the engravings; but we fear they are neither very 'correct' nor very 'satisfactory.' The origin of blight is alledged to proceed from the seeds of a fungus gaining admission into the pores of the straw, that are shut in dry, and open in wet weather;' and that by germinating there, as is supposed, but not demonstrated, they intercept the sap that was intended by nature for the nutriment of the grain. The observations on the deleterious effects of this malady, treat a local disease as a general one, and would have been much better omitted. Ought not the philanthropist, armed with the authority of age, experience, and philosophy, to have paused, ere he gave data to all-grasping speculators, by speaking of a sack of blighted wheat not yielding a stone of flour? On reading this, who can withhold a tribute of thanks to the engraver,* who seasonably detained the distribution of opinions more dangerous from their authority than their foundation in fact. We do not however wish to deny the reality of this blight last season; but its existence is enough to excite philosophical research, without exaggerating the extent of its ravages.

It is acknowledged that no information of importance relative to the origin or the progress of the blight could be obtained:' of course, nothing has been added to the observations of Fontana, except a few conjectures not always very original or recondite. The following, we confess, surprized us not a little:

This (the want of information) is not to be wondered at; for as no one of the persons applied to had any knowledge of the real cause of the malady, none of them could direct their curiosity in a proper channel. Now that its nature and cause have been explained, we may reasonably expect that a few years will produce an interesting collection of facts and observations, and we may hope that some progress will be made towards the very desirable attainment of either a preventive or a cure.'

'Explanation of the nature and cause of this evil.' (In other

In the preface, the author apologizes for the late appearance of his work by the neglect of the engraver, but it is a poor subterfuge to make this delay, or the alarming state' of the late harvest, a sufficient apology for the want of actual observations on the origin and progress of the disease:' there is neither modesty nor dignity in such finesse.

words, the presumed natural history of this supposed parasitic plant.)

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It seems probable that the leaf is first infected in the spring, or early in the summer, before the corn shoots up into straw, and that the fungus is then of an orange colour*. After the straw has become yellow, the fungus assumes a deep chocolate brown; each individual is so small that every pore on a straw will produce from twenty to forty fungi, and every one of these will, no doubt, produce at least one hundred seeds; if then one of these seeds tillows out into the number of plants that appear at the bottom of a pore, how incalculably large must the increase be ! A few diseased plants scattered over a field must very speedily infect a whole neighbourhood, for the seeds of fungi are not much heavier than air, as every one who has trod upon a ripe puff-ball must have observed by seeing the dust, among which is its seed, rise up and float on before him. How long it is before this fungus arrives at puberty, and scatters its seeds in the wind, can only be guessed at by the analogy of others; probably the period of a generation is short, possibly not more than a week in a hot season; if so, how frequently in the latter end of the summer must the air be loaded as it were with this animated dust, ready, whenever a gentle breeze, accompanied with humidity, shall give the signal, to intrude itself into the pores of thousands of acres of corn.'

The muse of Darwin himself could not have suggested any thing more fantastic! When will botanists leave the glittering poetic effusions of the imagination, for the language of reason and experience? Let us attend, however, to the discovery, which well merits to be placed with that ingenious doctor's theory of the windst. What physiologist has before treated of animated dust? and by what hitherto-undiscovered law of hydrostatics or pneumatics has dust become more volatile or buoyant by humidity? But, in candour, for the same reason that we reject this voyage of dust, and the subsequent vegetable impregnation by means of atmospheric humidity, we must also reject the supposed generation of insects, proposed too upon microscopic observations by Somerville. We pass over the appropriate reflections on the goodness of Providence, to notice the more original observation, that notwithstanding the ravages of this disease, the price of wheat immediately after years of great blight, has been very considerably under the average price of five years. This fact, illustrated by the example of the years 1725 and 1797, ought to obviate

This conjecture is incompatible with the sudden appearance of blight after a few days of forgy weather.

Since writing the above, the author has generously communicated his work to a respectable periodical Journal, with some additional notes, in which we had the mortification to find that even this supposition was borrowed from L'Abbé Tessier!! RLV.

Castled on ice, beneath the circling Bear,
A vast meleon spits and swallows air."

Bor. GARD.

the pretexts of speculators* for the present high prices of

corn.

We are told that the blight in corn is not peculiar to the climate of the British Isles, but that it prevails in Italy, Sicily, and New South Wales. We can add, that we have not only seen it in Italy, but in several parts of Switzerland; in the low lands of Languedoc, Guyenne, and many other parts of France; in the provinces of Biscay and Grenada, and on the banks of the Ebro, Tagus, and Douro, in Spain and Portugal; in short, it prevails in every country where there are frequently thick wet fogs, or a very humid atmosphere. The influence of the barberry bush in causing this disease, ought to be more minutely examined: but the supposition that the fungus is brought into the field in a few stalks of infected straw uncorrupted among the mass of dung,' is sufficiently refuted by the - subsequent confession, that the crops of the unmanured land were equally infected with those of the manured. Indeed, it is in contradiction to all that precedes: as, were it possible that it should be propagatel in this manner, the dung being invariably covered with mould long before the leaves of the corn appear, the nidus of this plant must then be in the earth, and not, as supposed, in the pores of the straw and leaves of

corn.

Sir Joseph boldly asserts, that

Although the seeds of wheat are rendered, by the exhausting power of the fungus, so leau and shrivelled, that scarce any flour ht for the manufacture of bread can be obtained by grinding them; these very seeds will, except, perhaps, in the very worst cases, answer the purpose of seed-corn as well as the fairest and plumpest

The spring wheat of Lincolnshire was not in the least shrivelled this year, though the straw was in some degree infected: the millers allowed that it was the best sample brought to market. Barley was in some places considerably spotted, but as the whole of the stem of that grain is naturally enveloped in the hose or basis of the leaf, the fungus can, in no case, gain admit

tance to the straw.'

Eighty grains of the most blighted wheat of the last year, that could be obtained, were sown in pots in the hot-house; of these seventy-two produced healthy plants, a loss of 10 per cent. only.' Does the right hon. president mean to establish, from this hot-house experiment, a rule for farmers? Does he count for nought the influence of light and heat on the process of germination? To render this experiment of any practical importance, grains of plump and blighted wheat should have been sown in pots of similar dimensions, and the quantity of flour which the respective ears produced, correctly weighed, to determine which was the most productive. From the analogy both of the animal and vegetable kingdom, we should declare the plump or healthy seed the most productive. The field, however, and not the hot-house, is the sphere for these experiments; as, most probably, an extra portion of heat is necessary to make blighted wheat vegetate. Good wheat will germinate in a day, or in seven, eight, or more days, according to the quality and temperature of the soil; in the latter case, we suspect that putrefaction instead of germination would take place in blighted wheat, some instances of which we have incidentally observed in granaries.

sample that can be obtained, and in some respects better; as a bushel will contain one-third at least more grains, and three bushels will go as far as four of large grain. The use of the flour. of corn is to nourish the minute plant from the time of its developement till its roots are able to attract food from the manured earth, for which purpose one-tenth of a grain of good wheat is more than sufficient. The use of plump samples for seed is unnecessary waste, as the smallest grains, such as are given to the poultry, will be found to answer the purpose of propagating the sort from whence they sprung.'

Before we venture to recommend this plan to general practice, it will be necessary to make a great variety of experiments in different soils and seasons, and that the results should be decisive beyond the possibility of doubt, respecting the positive utility of the adoption of such a measure; otherwise, the consequences might be too serious to be coolly anticipated. Admitting that one-tenth of a grain of good wheat may be sufficient for the purpose of germination (although this onetenth is better than the whole of a bad grain), yet it is not certain that the plant will be equally strong and productive at the time of harvest. We fear the contrary will be found the case; and we have repeatedly seen the fatal effects of sowing bad seed for clover, flax-seed, &c. Add to this, that however the one-tenth may nourish the minute plant from the time of its developement till its roots are able to attract food from the manured earth,' as far as relates to the quantity of gluten, yet the entire vegetable earth of which all seeds are composed, seems no less essential to the progress of fructification. This vegetable earth indeed appears to form the connecting medium between the plant and common earth: in other words, it serves the purpose of the stomach in digesting and assimilating the aliments of the plant to their proper vessels and juices. If this be the fact, any diminution of the earthy matter must be finally injurious to fructification. It may be observed also that the vegetation of seeds is different in this respect from that of roots, which fructify by section. It is indeed from the chemico-agriculturist, and not the botanist, that we should expect the illustration of this interesting point, by a series of well-conceived experiments, in which the agency of alkalis, acids, gases, light, &c. would be correctly investigated. The observations of Humboldt on this subject (in part refuted by Saussure and Berthollet) are more the result of theory and imagination than such as are admissible into practical philosophy.

With regard to the cause of blight here assigned, we regret that the few facts adduced are such as a sense of our duty to the public compels us to say are not 'satisfactory.' Our read

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