Blackwood's Edinburgh Magazine, No. 401, March 1849. Various

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СКАЧАТЬ and perfect it. Alongside of descriptive and systematic botany has sprung up the allied branch of Structural Physiology, and the use of the microscope has added to this the younger sister Histology; while these two together, calling in the aid of chemistry, have built up the further departments of Chemical Physiology and Chemical Histology – departments too numerous, too profound in their research, and too special in their several niceties of observation, for one head clearly to comprehend and limit them.

      And on the plant as it grows, and as a perfect whole, chemistry expends entire and most gifted intellectual lives. Of what the plant consists, whence it draws its subsistence, how it takes it in – in what form, in what quantity, at what period of the day – how the air feeds it, how the soil sustains it, why it grows well here and badly there – what are the nature, composition, action, and special influences of manures – where and when, and of what kind, they should be applied to the plant – how this or that effect is to be produced by them, and this or that defect remedied.

      But the life of the plant is an unravelled thread. The steam-frigate appears to live, and thunders as she moves, breathing fire and smoke. But the still life of the plant awes and subdues more than all this. Man may forcibly obstruct the path of the growing twig, but it turns quietly aside and moves patiently on. The dead iron and wood, and the forceful steam, all obey man's will – his intellect overmasters their stubbornness, and tames them into crouching slaves – but the life of the plant defies him. That life he can extinguish; but to use the living plant he must obey it, and study its wants and tendencies. How vastly easier to achieve a boastful triumph over the most stubborn mineral matter, than to mould to man's will the humblest flower that grows!

      And each new plant brings with it new conditions of life, new wants, new virtues, new uses, new whims, if we may so speak, to be humoured. The iron, and the timber, and the brass are always one and the same to the mechanist; but with the constitution of each new plant, and its habits, a new series of difficulties opens up to the cultivator, which only time and experience, and much study, can overcome.

      But mechanics also exert much influence upon the culture of the soil, and the rearing of useful plants. And though the greatest achievements of mechanical skill were not first made on her behalf, yet even the steam-engine may be said to have become auxiliary to agriculture; and the thousand ingenious implements which Northampton and York exhibited at their recent anniversaries, showed in how many quarters, and to how large an extent, the purely mechanical and constructive arts are expending their strength in promoting her cause.

      On meteorology, which studies the aërial meteors – registers, tabulates, and gives even a local habitation and a form to winds, hurricanes, and typhoons – the progress of the navigator much depends. They hinder or hasten his progress; but he overcomes them at last. But atmospheric changes are vital things to the plant and to the soil. Where no rain falls, the plant withers and dies. If too much falls, it becomes sickly, and fails to yield a profitable crop. If it falls too frequently, though not in too large quantity on the whole, one plant luxuriates and rejoices in the genial season, while another with difficulty produces a half return. If it falls at unseasonable times, the seed is denied admission into the ground in spring, or the harvest refuses to ripen in the autumn.

      So the warmth and the sunshine, and the evening dews and the fogs, and the electric condition of the air – its transparency and its varying weight – and prevailing winds and hoar-frosts, and blights and hail-storms, and the influence of the heavenly bodies on all these conditions – with all these things the interests of the plant and the soil demand that scientific agriculture should occupy herself. On every single branch of knowledge to which we have alluded, the power and skill profitably to influence the plant are dependent.

      And for what purpose does the plant spring up, the soil feed and nourish it, and the blessed sun mature its seeds? To adorn, no doubt, the surface of the beautiful earth, and to keep alive and propagate its species; but principally to nourish the animal races which supply food and yield their service to man. And, upon the study of this nurture and feeding of the animal races, how much intellect has been expended! Has the stoker who heaps coals upon the engine fire, and turns one tap occasionally to maintain the water-level in the boiler, or another to give passage to the steam – and thus keeps the pile-driver, or the coal-drawer, or the tin mine, or the locomotive, or the steam-boat, or the colossal pumps of the Haarlem lake, in easy and continuous operation – has he, or has the man who curiously watches his operations – have either of them any idea of the long days of intellectual toil – of the sleepless nights, during which invention was on the rack – of the mental dejection and throes of suffering, under which new thoughts were born – of the lives of martyred devotion which have been sacrificed, while, or in order that the machine, which is so obediently simple and easily managed, was or might be brought to its present perfection? Yet all this has been, and has been suffered by men now gone, though the ignorance of the humble workman, little more thoughtful than the iron he works with, fails either to feel or to understand it.

      And so too often it is with you who feed, and with you who look at the simple process of feeding stock. As the turnip and the barley, and the oats and the linseed, and the beans, are placed before the almost perfect short-horn, or the graceful Ayrshire, or the untamed West Highlander, or the stately stallion, or the well-bred Leicester or Cheviot ram, or the cushioned and padded Berkshire porker – how little do you know or think of the science, and long skill, and intellectual labour, which have been expended in preparing what is to you so simple! It is not without and beyond the ranks of the agricultural community only that we need look for those who lessen the intellectual character of rural industry, and of the rural life. Too many of our practical men, even of high pretensions, are themselves only the stokers of the agricultural machine; and, like ungrateful and degenerate children, in their ignorance deny the head of the mother that bred and fed them.2

      What are the functions of the animals you rear – what the composition of their several parts – what the nature of the food they require – what the purposes it serves – what the proportions in which this or that kind of food ought to be given – what the changes, in the kind and proportion, to adapt it to the special habits and constitution of the animal, and the purposes for which it is fed? Are these questions deep? Yet they have all been thought over and long considered, and discussed and disputed about, and volumes have been written upon them; and the chemist, and the physiologist, and the anatomist have, unknown to you, all laboured zealously and without wearying, in your service. And what you now find so simple only proves how much their sciences have done for you. They have fitted the machinery together, you but throw in the fuel and keep up the steam.

      With the rearing of stock, and the improving of breeds, practical men are, or fancy themselves, all more or less conversant. How much warm and persevering genius, guided by purely scientific principles, has been expended upon our improved shorthorns and Leicesters! Are the whole lives of a Collins, or a Bakewell, or a Bates, nothing to have been devoted to pursuits like this? That these were practical men, and not scientific, and that what they have done is not a debt due by agriculture to science, is the saying of many. Men who have never read a book can do, by imitation, what the patient services and skill of other men discovered, and perfected, and simplified. But in this they are only stokers. The improvers were sound and cautious experimental physiologists, guided by the most fixed and certain principles of animal physiology; and it is the results at which these men arrived that have become the household words of the stokers of our day, who call them practice in opposition to science. If science could forget her high duties to the Deity, and to the human race, she might leave you and your art to your own devices.

      Need we allude to the conditions of animal life – in a state of health, and in a state of disease; to the varied constitutions of different races and varieties; to the several adaptations of food, warmth, and shelter which these demand; and to the extensive course of study which is now required to furnish the necessary resources to the accomplished veterinary surgeon? Yet would any breeder be safe for a moment to invest his money in stock, in a country and climate like ours, had he not, either in books, or in СКАЧАТЬ