158 AFFINITY groundless defence to his suit ; but the require- ment of it does not always accomplish the de- signed object. AFFINITY, the imputed relationship which exists in consequence of marriage between the husband or wife and the kindred by blood of the other. Thus, for example, the wife's kin- dred bear the same relation by affinity to the husband that they bear to her by consanguinity. Affinity also exists between the husband and one who is connected by marriage with the blood relations of the wife. Two men, for in- stance, who are married to sisters are related by affinity, but there is no such relationship between the blood relations of the husband and those of the wife, and it ceases properly when the husband or wife dies without leav- ing issue. Affinity is significant in the law because it constitutes a disqualification of judges or jurors, equally with consanguinity. When such a disqualification exists, the judge cannot act even with the consent of both par- ties ; and if he does, the judgment may be va- cated. Thus it has been held in New York that there was a disabling affinity between a judge and the defendant in a cause before him, because the defendant's deceased husband was a first cousin of the judge, and the son of de- fendant by that husband was still living. This living son preserved the affinity, which other- wise would have ceased on the husband's death. Affinity is also significant in the laws of mar- riage. The ecclesiastical law made certain marriages unlawful though they were con- tracted between persons whose relationship to each other was very remote. Though the statute of 32 Henry VIII., which has virtually furnished the rules of the English law on the subject ever since, forbade the ecclesiastical court to impeach the validity of any marriage between parties who were without the Leviti- cal degrees, yet it was always held under it in England that affinity was an impediment to the same extent as consanguinity ; and out of this interpretation of the statute came that rule of the law which has been so much discussed and assailed in England, that a man may not marry his deceased wife's sister. The reason given was that the marriage made the wife's sister the husband's sister ; and although in the other branches of the law, with respect to ju- dicial officers for example, the death of either party destroys the affinity and the disqualifi- cation, yet the same result has not been con- ceded in matrimonial cases. AFFLMTY, Clicminil. the name given to the force which combines together chemical ele- ments so as to form compounds. Of its real nature or essence we are entirely ignorant, as we are of the essential nature of other material forces. The term chemical attraction has also been applied to this force, on the hypothesis that it draws together chemical atoms. In many cases there can be no doubt that the chemical particles come nearer together when they combine: thus if two volumes of hydro- gen and one volume of oxygen be caused to unite, we do not get three volumes of steam, but only two; that is, the particles have ap- proached so much closer in combining as to occupy but two thirds of their former space. In other cases, however, compounds are found to occupy exactly the same space that their ele- ments did before combination, and sometimes they fill even a greater space. Hence the term chemical attraction has been thought objection- able. Chemical affinity is that link or tie which binds together unlike kinds of matter, in such an intimate manner that the properties of the elements are lost, and a compound with new properties is produced. It is in this that it differs from cohesion, which only unites or aggregates similar particles without altering properties. The particles in a piece of iron or sulphur are I held in union by cohesion ; but when sulphur I and iron combine chemically, both elements disappear, lose their properties and identity, and a new compound is formed the sulphuret of iron. Newness of properties in the com- pounds formed is the distinguishing peculiarity of chemical affinity. It obliterates the char- acteristics of the elements, and generates new properties in the product. Cohesion is usually said to act between homogeneous particles, as in the cases just cited of sulphur and iron ; but it may also act between dissimilar substances, as where silver is inlaid with steel, or copper metal united to tin, or iron coated with zinc, or wood joined to glue, or paper to paste, or pitch to the fingers. These, however, are mechanical com- binations ; there is no destruction of the prop- erties of the combined substances, and those of the combination are not new, but are the same as the properties of the constituent substances, each of which retains its individuality. The force of gravitation is brought into play be- tween masses of matter at all distances ; chem- j ical affinity acts only when the elements are ' in contact or at insensible distances. For this reason affinity is most energetic when one or both of the elements are in a state of solu- tion, the approach of the- atoms being then most perfect. It was once thought that chem- ical affinity could not take effect without the intervention of solution; and although the statement is generally true, yet there are some substances whose affinities are so intense that they will unite even in the solid state when made to touch each other. The action of affin- ity is heightened, modified, and suspended by various other causes. Among these heat is most potent, and most easily available in the laboratory and chemical manufactory. Thus carbonic acid and lime unite strongly at com- mon temperatures, forming marble or lime- stone, but at a red heat their affinity is annihi- lated and they separate. On the other hand, potash and sand will not actively combine at ordinary temperatures, while at a red or whit. heat, at which they are melted, combination takes place and glass is formed. Light also in- fluences affinity, promoting combination and
