so do they carry it to a higher state of organization, and bring it nearer to the nature of man himself. Hence they are less and less fitted for effecting those changes in the functions and states of organs, which form the objects of medicines ; but they are therefore the better suited for affording materials of renovation to the exhausted frame; as we may see by the large proportion of the Vertebrata employed for food. That a greater number of medicines were formerly obtained from the animal kingdom, is not therefore to be ascribed to their powers having been supplanted by a more abundant and perfect supply from the vegetable and mineral kingdoms. But then, the general ignorance of both practitioner and patient allowed the former, by means of loathsome remedies, to operate on the imagination of the latter ; in hopes of producing those changes in the state of disease, which his knowledge did not tell him how otherwise to effect. The reign of ignorance is not yet passed ; but more elegant modes have been successively devised, for producing the same results; by those who have less excuse than their pre- decessors for such practices.
The exceptions to the above observation, are but few: musk and castor still continue to be used ; but these seem to be secreted by the respective animals for acting as stimulants to some of their own functions: certain sub- stances are employed as emollients, and operate chiefly by their mechanical properties ; to these may be added carbonate of lime, secreted in large quantities by lower tribes of animals, as a defence against their numerous enemies; but which the improved state of chemistry has shown, can be procured of equal purity and with greater facility from the mineral kingdom. So few articles being now obtained as medicines from the animal kingdom, it is of less consequence to ascertain whether there be that connexion between structure and its properties, as we have
