It is a curious fact, that the true has always been more opposed at the outset than the false; the circulation of the blood and vaccination nearly lost their discoverers credit and practice, while some vender of quack medicines makes a rapid fortune. This may perhaps be accounted for, simply, that the impostor addresses the multitude, while the scientific discoverer appeals to his brethren in knowledge, all of whom are inclined to deny, what, if admitted, must show, that a great part of their own research and acquirement has been in vain; still he who trades on human credulity will have a good stock on hand, especially when the lure held forth is that of gain.