In a review of a Biography of Sir Astley Cooper, in the "Quarterly," an experiment there described was characterized by the writer as "Hellish." We have no desire whatever to use unnecessarily strong terms; nor do we think that the one above mentioned was too strong for the case to which it referred; but we think that this extremely fallacious mode of investigation will be most quickly abandoned, by meeting fairly and in a mild and moderate spirit any allegations in its favour. Dr. Hull, of Norwich, and several other eminent persons, have expressed their dissent from this mode of inquiry. Sir Isaac Newton considered cruelty to animals a violation of Christian charity[25]. For our part, we have several times stated _our willingness to discuss_ any class of experiments which may be selected; for, although we may not express ourselves so well as a late writer in the "Quarterly," yet to our minds heaven and hell do not present an idea of greater contrast than that afforded by the notion—that laws which govern the whole animal kingdom, and which present, at every moment, accumulating evidences of goodness and mercy, should be auspiciously sought, much less have their nature and relations developed, by torture of those very objects for whom such benevolent provisions have been designed. We have paid some attention to this subject; and it is very curious to remark, that observations or experiments, when they cease to be cruel, become instructive. Indeed, if we reflect for a moment, we shall see that it must be so. If we desire to know the actual nature of any living being, it must be as if we were ourselves unseen—that is, that the animal may be in a _perfectly_ undisturbed condition. The moment we _lose_ this, elements of interference immediately arise and fog our reasoning; and the more refined the inquiry, the more the avoidance of disturbance becomes essential: in fact, the utmost success in obtaining the conditions _philosophically_ necessary, depends on maintaining as nearly as possible the natural condition—that is, the comfort of the animal; so that the conditions necessary on philosophical grounds, and those which we regard as still more important after all, coincide. In every path of life, there are unpleasant duties; and it might have happened that the functions of animals could only have been investigated by the means we would repudiate: but the simple truth is, that it is demonstrably otherwise.