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fail of success, he is precluded from pleading any obstructions that might arise from the engagements of the crown with foreign nations. The conclusion reverts, with accumulated force, against the wisdom and mildness of his administration. Hitherto it has been only marked by the blood of the principal nobility, and universal oppression of the people. There can be no increase of wealth in a country where industry is effectually discouraged, and no man's property secure. There can be no domestic content or happiness among a people, one half of which are spies upon the other. Racks, gibbets, and dungeons are the emblems and resources of his government. It is but the natural consequence of such a government that the Portuguese, with many advantages of personal character and local situation, are the meanest and most degraded people, and the crown of Portugal the least respected, of any in Europe.

Sir Benjamin Keene, who knew the Marquis of Pombal early in life, emphatically describes him as a conceited and puzzled head. How far the intrepidity of his spirit may deserve the opinion conceived of it, can only be determined by experiment. He may have penetration enough to see into the genius of the people he treats with, and may proportion his own firmness to their apparent want of it. But this part of his character has never been fairly put to the proof, at least by Great Britain. If any farther presumption in favour of his abilities should be drawn from his having raised himself to an absolute dominion over his country, and maintained it so long, it may be weakened by considering, that the government of Portugal is despotic, and that the talents and intrigues which ingratiate a servant with his master are sometimes the least likely to qualify him for the government of a kingdom. He is sagacious; but having seldom the good fortune to reason upon right principles, his sagacity, in many important instances, serves only to mislead him. He has had experience; but ill-considered facts, without principles or instruction, have perplexed his understanding. Of this we see a signal instance in the conclusions he drew from the establishment of one or two great exclusive trading companies in England and Holland. If his zeal for the good of his country be ardent, it certainly is not luminous. He is industrious beyond measure ; but his industry, supported by a jealousy of all competition with him, has this dangerous effect, that while he engrosses more of the executive branch than he can possibly support, no one office of the state is executed as it should be, and business stands still. It is also to be apprehended, that, by his excluding the inferior ministers from confidence and information, the kingdom at his death will probably be left without a man in office, in any way qualified to succeed him. This is the common policy of favourites; but it presents no idea of a great, superior mind. Considering his uniform plan of conduct towards the natural allies and natural enemies of Portugal, we may allow him a degree of personal intrepidity, which does no great honour to his discretion. The proofs of it, in his internal government, are more equivocal. It does not seem to require much firmness or resolution to employ an armed force in the oppression of a poor, spiritless, unresisting people. Tyrants, who have trembled on their thrones, have done it with success.'



Art. VII.-1. Protoplasm : or Life, Matter, and Mind. By

LIONEL S. BEALE, M.B., F.R.S. London : 1870. 2. Disease Germs: their Real Nature. An original investiga

tion by LIONEL S. BEALE, M.B., F.R.S. London: 1870. 3. Pulmonary Consumption: its Nature, Varieties, and Treat

ment. By C. J. B. WILLIAMS, M.D., F.R.S., and C. T.

WILLIAMS, M.A., M.D. Oxon. London: 1871. NO for the least wonderful of the many marvels that have been,

more or less perfectly, brought into clear light by the persevering and ceaseless labours of human intelligence, is the composition of the blood, the thick crimson liquid which sustains the powers of the living animal, and which courses for that purpose, in never-stopping stream, through all parts of the frame so long as its vital activity lasts.

The problem which has been worked out in the composition of the blood of the living animal is the production of a substance containing within itself all that is required for the maintenance and renovation of the various fabrics of the body and for the support of their especial offices, in a form convenient for the circumstances in which the work has to be done. It is liquid because it has to be distributed to the several fabrics that it has to nourish, through a service of branching tubes; and it is complex because it has to contain all the ingredients that are needed for the constitution of those fabrics in their vast diversity,-flesh, membrane, fat, gristle, bone, nerve, and brain.

The blood of the living animal is essentially food which has been compounded by vital elaboration, and in that elaborated state thrown into the actual channels of the living frame, where its work of sustenance has to be accomplished. But not only this. The blood is also, itself, in strict accuracy, an integral part of that ' living frame.' In the blood, the complex substance has received its ultimate perfection and finish in the impress which endows it with vital condition and power, and has become in the physiological sense a “ living thing.' Of the fact of this endowment with potential life there is no question anywhere; but there is question and dispute as to what the exact process and method of transformation are. A contest is yet waged between antagonistic schools of physiologists, who cach assume that they are at least on the road to the inner shrine and explanation of the mystery. The one of these schools insists that life is but a more complicated manifestation and development of molecular and material forces--a property



of material substance when it has been raised into the sphere of sufficiently advanced and matured complexity. The other affirms that life is a superadded and altogether independent Power, which acts through the instrumentality of elaborately perfected material, but is altogether apart and distinct from the intrinsic properties of material substance. In looking from without upon the strategy of this contest, the non-combatant easily perceives that both parties in the conflict are dealing with what some German thinkers of the day call the ‘Aberglaube' of the matter; the essentially inexplicable and undemonstrable portion of the subject. Both the materialists and the vitalists may entrench themselves on the opposite heights of the field to which they have betaken themselves; but from their entrenched fortifications each has to admit that one common fact of philosophy underlies both their positions, namely, an utter inability to reach the real heart of the mystery.

The blood, or perhaps in more strict accuracy the chyle, which is incipient blood-the sublimed and liquefied food on its way to be mingled with the stream of the circulation—is, then, the seat of the first manifestation of vital endowment. In it the subtle change, whatever that change may be, which converts nutritious material into living substance, takes place. It is, at any rate, the immediate penetralium in which the mystery that is still the aspiration, if not the reproach, of physiological science lies concealed, and in which the work of further investigation has to be mainly carried on.

But the blood, which is thus the seat of the first development and manifestation of life, is not, it should be remarked, altogether alive. It consists of living parts and dead parts, intimately mingled with each other. Eignt pounds and a half of every ten pounds of healthy human blood consist of an almost clear liquid spoken of as the serous part, or serum, the remaining pound and a half being an infinite number of very minute bodies, partly colourless and partly red, and individually so small that their existence in the liquid is only discovered when very powerful microscopes are employed in the observation. The colourless serum, and the microscopically granular or corpuscular constituent, are properly the dead, and the living, portions of the blood.

The serous liquid is simply the perfected extract of the digested food rendered mobile and fluid by the addition of a very large proportion of water. Of the eight pounds and a half which have been spoken of, no less than eight pounds are water, and could be distilled off as water alone. The remaining half-pound, which gives serosity to the water, is indeed almost entirely albumen derived from the food-a complex substance all but identical with the white of eggs, and capable like it of being coagulated by heat. Thus constituted it is the great pabulum or plastic base out of which the organised substance of the living body is constructed. In the egg of the oviparous animal the deposit of albumen is arranged round the germinal yolk to be ready there when the first work of fabrication is entered upon in building up the chicken. In the blood the albumen is provided for exactly the same purpose: it is food in the ultimate state of preparedness for conversion into textures of the widest range of diversity. The water of the serum is merely the vehicle furnished to keep the albumen moveable and thin, and in that way ready for its proper officeready to be poured along the system of pipes laid down for its conveyance through all,

and to all, parts of the frame, and to be in that way thrown into close and intimate relation with all the films, fibres, and textures that have to be continually refreshed and renewed by its plastic agency:

But the serous liquid of living blood is viscid from the presence of something yet more tenacious and plastic than albumen. The serum of the blood coagulates of its own accord when the blood is caused to flow out from the warm vessels of the living body into cooler air. It separates into a

. clear thin liquid, which does then consist of pure albumen and saline principles mingled with water, and into a clot composed of

a a dense, fibrous, sticky substance, which is albumen pushed one step farther towards the living condition. The albumen, thus rendered coagulable and capable of solidifying into a fibrous clot without the aid of a high temperature, is not chemically changed in any appreciable way from that which still remains liquid in the thin serous residue. The chemist is not able to discover any intrinsic atomic or molecular difference between the two; and the physiologist, in his turn, is able to say nothing more about the matter than this—that the albuminous principle derived from the food, without any appreciable or discoverable change of material composition, without the addition or subtraction of any material ingredient, has, in the bloodstream of the living body, been made more plastic and organisable, more adhesive and ready to be converted into fibre, and membrane, and texture.

It is a notable fact that a singularly small quantity of this fibrinous principle is sufficient to make the blood thick and adhesive enough for all practical purposes. In the fifteen pounds of blood that are contained in the body of a man of ordinary stature there is not more than half an ounce of adhesive fibrin at any one time. But it must be understood that the fibrin which is there is being continually expended in practical service, and at the same time as continually formed auew out of the relatively large store of albumen contained in the „serum. The fully matured fibrinous principle is absolutely essential for the plastic work which is involved in organisation, But too large an amount of it at any one time in the channels of the circulation would be of necessity fatal to the orderly accomplishment of the process. A very slight increase over the ordinary allowance of standard health would render the entire mass of the blood so thick and unruly in its adhesiveness, that it would be ever prone to stagnate in the minute channels and passages it has to permeate. This is abundantly shown in certain disorders of the inflammatory and rheumatic class, where the derangement is primarily due to the too rapid and abundant conversion of albumen into fibrin.

In the arrangements which are incident to the condition of perfect health an ample reserve of albuminous material is kept constantly in store, and fresh portions of this reserve are worked up into the more elaborate and quasi-vital condition of adhesive fibrin exactly as this is needed for the construction of the more fibrous textures of the frame.

Thus much of the nature of the blood is made out by very simple observation, unaided by any of the more refined instruments of philosophical research. But the other, and living, portion of the blood can only be studied by the skilful employment of very powerful microscopes. When a minute droplet of freshly drawn blood is placed on a slip of glass, and is there pressed out into a thin film and then highly magnified, it is at once seen that a countless myriad of minute, round bodies are floating about in the liquid, the greater proportion of them being of a yellowish-red hue, and therefore very conspicuous in the clear serum, from the effect of contrast, but a smaller proportion of them being almost without colour. These, in default of any better name, are called the

little bodies,' or ' corpuscles,' of the blood. Various attempts have been made to give some clear idea of the surpassingly minute dimensions of these blood-corpuscles. But it must be confessed that both observation and description are alike inadequate to do so.

It does not accomplish very much to say, as is often done, that ten millions of them could lie tessellated together as a pavement upon the surface of a square inch, and that from twenty-five to thirty-two hundred of them could be ranked in single file within the linear extent of an inch.


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