HOW frequently it happens that those natural productions with which we are to a certain extent superficially familiar, are to a great many not only uninteresting, but are regarded as subjects more or less beneath their notice; and by others as deleterious to the human race, and therefore to be cautiously used or scrupulously avoided. Another peculiarity is, that the more we are accustomed to them, the more our interest wanes, and probably at last degenerates into apathetic indifference. We can only attribute these ignorant conceits and apparently unaccountable obliquity of judgment to two causes: an assumption of wisdom, and an unenlightened mind, unwilling to learn and loath to improve. Another hindrance which to a considerable extent precludes the study of what one may truthfully designate every-day subjects, is the restless furor for artful counterfeits of science, which are nothing else than the emanations of vain and visionary minds mixing together, as it were, an amalgam of truth and error. The present age is wonderfully productive of these eccentric ideas, while at the same time it is unhappily pregnant with the most unnatural and anti-healthful habits. The mystified authors take good care to run into the wildest extremes, so that their marvellous schemes and quaint devices (fortunately for their fellow-creatures) cause them to be justly derided by the thoughtful and disregarded by the sensible, though not a few are caught by the tinsel.