861 



INFECTION. 



INFINITE. 



in which state they were able to render the shock of cavalry entirely 

 unavailing. Large divisions of these troops accompanied the army of 

 Charles VIII. into Italy, in 1494, where their good conduct and dis- 

 cipline greatly contributed to raise the reputation of the 'infantry to its 

 ancient standard. 



The superiority of this class of troops consists in their being able to 

 act on ground where cavalry cannot move ; and it is obvious that the 

 latter must, at all times, have been nearly useless in the attack and 

 defence of fortified castles or towns. Even when the cavalry were held 

 in the highest estimation it was sometimes found convenient for the 

 knights to dismount and act as infantry. Froissart relates that at the 

 battle of Cressy the English troops were formed in three lines, con- 

 sisting of men-at-arms who fought on foot and were flanked by archers. 

 At Poitiers and Agincourt also the men-at-arms engaged in a similar 

 manner. 



The Spanish soldiery, probably from being almost constantly en- 

 gaged in warfare with the Moors, had early acquired considerable 

 reputation ; and the gallantry of the troops on foot, in keeping the field 

 after the cavalry had retired, has been supposed, though this opinion 

 of the origin of the name is now rejected as fanciful, to have been 

 commemorated by the designation of infantry, which was bestowed 

 upon them, it is said, in consequence of their having been headed on 

 that occasion by an Infanta of Spain. The great share which tlie 

 Spanish forces had in the wars carried on both in Italy and Flanders 

 iluiing the reigns of Ferdinand, Charles V., and Philip II.; their 

 steady discipline, and the success which resulted from the association 

 of musketeers with pikemen in their battalions, caused the infantry of 

 Spain to be considered, during many years, as the best in Europe. But 

 the rivalry in arms between the Emperor Charles V. and Francis I. of 

 France, and the connection of Henry VIII. of England with both, led, 

 in the several states of those monarchs, to the adoption of the i: prove 

 which had been introduced by the Spaniards. It may be added 

 that the practice of keeping up standing armies composed of men 

 trained in the arts of war under a rigid system of discipline, together 

 with the universal adoption of the musket, has now brought all the 

 infantry of Europe to nearly the same degree of perfection. 



In 1859 the English army numbered 86,983 infantry troops, exclu- 

 sive of engineers and artillerymen, many of whom serve on foot; 

 besides those serving in India, under the name of the East Indian 

 Army. 



INFECTION is the contamination of the atmosphere or other inert 

 substances by the deleterious or offensive qualities of malaria, the 

 matter of contagion, effluvia from putrid animal or vegetable sub- 

 stances, Ac. Some of these are at once recognised by the smell, or by 

 chemical analysis, but the presence of others IB known only by tin- 

 diseases which they produce. The same means however may be 

 applied in many cases for preventing the injurious effects of both 

 , : ..-.. 



The most important and valuable method of disinfection is ventila- 

 tion, and, whatever other may be added to it, this should never be 

 neglected. The apartment, or whatever requires to be purified, should 

 be exposed to a constant and free current of fresh air, till every trace 

 of odour is completely expelled, or as long as any emanation is going 

 on. The reputation of chlorine, acids, lime, charcoal, Ac., as dis- 

 infectants, depends on their property of decomposing the offensive 

 gases which are so often mixed in the atmosphere with the matter of 

 infection, but it is questionable whether they have any influence on 

 the infectious particles themselves. However as the emanations from 

 putrid substances render the body peculiarly liable to the reception of 

 infection, some of these means should be employed where any offensive 

 smell is present. Fumigations with aromatic substances, as camphor, 

 Ac., are perfectly useless, only serving to conceal the smell, but having 

 no influence either on it or the infectious particles. Perfect cleanli- 

 ; - of the greatest importance ; every portion of the room or house 

 should be carefully and frequently washed with hot soap and water ; 

 clothes and everything removable should be immersed in hot water, 

 and after being well washed should be exposed for a long time to the 

 open air, or sprinkled with chloride of lime ; the walls and ceilings 

 should be whitewashed, and beds, bedding, Ac., cleaned and exposed in 

 the open air. Dr. Henry has rendered it probable by numerous ex- 

 periments that the infectious qualities of substances which cannot be 

 conveniently washed, as trunks, packages of valuable merchandise, Ac., 

 may be sufficiently destroyed by exposing them to a dry heat of 200 

 for (ot less than an hour. 



The following are some of the agents which are employed for the 

 purpose of destroying infectious matters of various kinds : 



Chlorine. This gas has a great affinity for hydrogen gas [CULOKINE], 

 and as the latter forms so conspicuous an element in infectious com- 

 Is, they are destroyed when exposed to the agency of chlorine. 

 me is especially applicable where infectious substances exist in 

 the atmosphere. It may be employed by generating it from the 

 ion of common salt with peroxide of manganese and oil of 

 vitriol, or by mixing red lead with dilute muriatic acid. These pre- 

 paration* however require c.intion, and the more common plan is to 

 lie solutions of chlorinated lime or soda. These solutions may be 

 appli' . and vessels may be rinsed out with them. They 



1* diluted and linen rinsed otit in them. 



Pcrmanyanata of todti andpotath. These substances are ^powerful 



oxidisers. Wherever animal and vegetable matters exist in a state of 

 decomposition, they oxidise the hydrogen and nitrogen, forming nitric 

 acid and water. They are sold under the name of " Condy's disinfect- 

 ing fluid," and are exceedingly useful where solid or liquid infectious 

 matters have to be dealt with. They speedily render the matter of 

 cesspools, drains, and sewers, perfectly innocuous. They may be also 

 employed for the purification of water, and by their action on organic 

 matters, can be employed as a test for the purity of water. The dis- 

 infecting quality of permanganic acid depends on the presence of ozone 

 in this acid, which is readily given up to the organic matters with 

 which it comes in contact. 



Chloride of zinc. This substance has the power of arresting change 

 in decomposing animal and vegetable substances, and may be employed 

 for this purpose, but it does not act so perfectly as the foregoing 

 substances. 



Perchlaride of iron. The salts of iron have all a great power of 

 combining with organic matters, and arresting the progress of decom- 

 position, and also of destroying infectious matters. It is one of the 

 cheapest substances that can be employed for disinfection on a large 

 scale, and is the compound recommended to the Metropolitan Board of 

 Works for deodorising the Thames. 



Sulphurous acid. This acid is formed by leaving sulphur in the 

 open air, and acts as a disinfectant by combining with oxygen, and 

 becoming converted into sulphuric acid. It cannot however be used 

 in rooms where persons are breathing on account of its suffocative 

 action. 



Sails of various kinds arrest decomposition, as nitrate of potass, 

 chloride of sodium, sulphate of zinc, Ac., but are not to be recom- 

 mended as disinfectants. 



Coal tar, Creosote, and Carbolic acid have all a power of combining 

 with animal and vegetable substances and preventing then- decompo- 

 sition. Creasote is especially recommended to prevent the smell from 

 cancerous sores. 



INFEFTMENT, in the law of Scotland, from the same origin as the 

 English term feoffment, expresses the ceremony by which a person 

 succeeding to another by descent, settlement, or conveyance, is invested 

 in any heritable or real property. This ceremony was, until quite 

 recently, as pure a feudal usage as it ever had been in the days when 

 the almost universal inability to write suggested symbolical modes of 

 changing possession. A number of persons had to proceed to the 

 ground, consisting generally of the solicitor who prepared the titles, 

 and his clerks, who had the following parts to act. One was the bailiff 

 of the superior, and a commission authorising him to act in that 

 capacity was read over. Another party acted as the procurator or 

 representative of the purchaser. The bailiff lifted some fragments of 

 earth and stone from the soil and handed them to the procurator, as 

 symbols by which, according to the authority given to him, he made 

 over possession of the lands to the new owner. The receiver of the 

 symbols then placed a coin of the realm in the hands of another party, 

 who must have been a notary public this being the form in which a 

 protest is taken in the hands of a notary in Scotland. Two other 

 parties acted as witnesses. The ceremony, with the authority on which 

 it proceeded, was narrated in a deed called an instrument of sasine, in 

 which the notary publicly attested the transaction. The preservation 

 of this cumbrous ceremony down to so late a period was owing to its 

 connection with the admirable system of registration which has kept 

 the commerce in real property in Scotland on so clear and secure a 

 position ; for the whole ceremony went for nothing unless the instru- 

 ment were recorded in the Register of Sasines within sixty days after 

 the ceremony. This registration was, and in modern usage is, the 

 criterion of preference ; for the person whose sasine is first registered 

 has the absolute title, all questions as to the fairness of the transaction 

 being pecuniary questions to be settled apart from the title to the 

 lands. The cumbrous ceremony mentioned above has been rendered 

 unnecessary by modern legislation. Conveyances and other deeds are 

 now, in most cases, registered themselves ; the public registration of 

 the deed, or of instruments setting out the nature thereof, or other- 

 wise analogous to the instrument of sasine, coming in place of the 

 infeftment and registration formerly in use. 



INFINITE, INFINITY, INFINITESIMAL, INFINITESIMAL 

 CALCULUS. The word infinite is literally " without bounds," and 

 when applied in an absolute sense to magnitude means that its quantity 

 is utterly unlimited, so that there is no conceivable and determinable 

 magnitude but what is less than the infinite magnitude. 



The notion of infinity is therefore at first purely negative, but it 

 does not long remain so : for we are forced upon what we take the 

 liberty of calling a definite notion of infinity, by our consideration of 

 time, space, and number. We cannot, if we would, annihilate our 

 conception of space, or confine it within certain limits ; nor can we 

 suppose duration to have an end. Even if we imagine our own annihi- 

 lation we cannot rid ourselves of the idea of something else existing, 

 with the permanent conception of unbounded space and time. If we 

 try t'> conceive all sentient existence at an end, we know from reasoning 

 that it may be we ought to suppose also the annihilation of space and 

 time : but the constitution of our minds will not permit it, and so long 

 as we exist to think, even about our own non-existence, the reality of 

 space and time will prevent our conceiving their destruction. Whether 

 the preceding be good or bad metaphysics is perfectly indifferent in an 



