In testing these opinions respecting the influence of climate upon crime, we are obliged, to some extent, to have recourse to international statistics. But these statistics, as has already been pointed out, owing to the diversity of customs, laws, criminal procedure, and so on, do not easily admit of comparison. So much is this the case that we shall not make the attempt as far as these statistics have reference to crimes against property. In this field no satisfactory result can, at present be obtained. The same remark holds good in relation to all offences against the person, with the exception of homicide. This, undoubtedly, in an important exception; and it arises from the fact that there is a greater consensus of opinion among civilised communities respecting the gravity of homicide than exists with regard to any other form of crime. Murder in all its degrees is a crime which immediately causes a profound commotion; it is easy to recognise; it is more likely than any other offence to come to the ears of the authorities. For these reasons this crime lends itself most readily to international comparison; nevertheless, differences of judicial procedure, legal nomenclature, and different methods of classification stand in the way of making the comparison absolutely accurate. These differences, however, are not so great as to render comparison impossible or worthless; on the contrary, the results of such a comparison are of exceptional value, and go a long way to determine the question of the effect of climate upon crimes of blood.