those whose liberty might, on surgical examination, prove dangerous to the unwary; _obsta principiis_ is as good a maxim in law as in physic. One Surgeon attached to each police office, for this, and other evident purposes, would be materially useful and not considerably expensive. We have observed in another place[149] on the attention necessary to be directed to prison discipline, as it respects the health of criminal or unfortunate prisoners; but the subject is so much before the public on this and other points, that we do not think it necessary to enlarge upon it here. It is not so, however, in other cases to which legislative attention might be advantageously directed. Sir _Robert Peel’s_ Bill for regulating the working hours of children in the cotton factories, might in some of its enactments be safely extended to many other branches of trade, more especially when contagious diseases are found to exist in large collections of people confined to a very small space. This observation applies also to infectious diseases breaking out in schools; at present the discretion of the master is the only security to the public: in the higher class we have no doubt that this discretion is well exercised; but there are others where, gain being the only object, the speculator will rather risk the lives of the unfortunate children committed to his charge, than the chance of their being permanently removed from his precarious protection.[150] We are well aware that any adequate remedy for these evils would require the most serious attention of the most experienced ability; but because the task is difficult, we do not think it impracticable; and where human life, in its most interesting and useful forms is at stake, we are assured that labour, however thankless in its outset, will ultimately meet its reward in the approval of society. Having thus ventured to suggest some measures which seem calculated to secure and promote the public health, we may be allowed to glance at the impolicy of any tax which has a tendency to deprive the lower orders of those articles which are essential to it; the salt duties immediately suggest themselves as a lamentable instance of such impolicy: salt is to the poor an indispensable part of their diet; it is essential to their bodily health, to the preservation or composition of bread, butter, cheese, meat, fish, and almost every article of their food, and its utility is always greater in proportion to the scantiness, and nutritive deficiency of their diet.[151]