Had Mr. Darwin written a work on the change of species, as determined by observation and experiment, without any other object but that of advancing natural science, he would have obtained a high place among philosophical naturalists. But after reading his work in which the name of the Creator is never distinctly mentioned, we can hardly believe that scientific truth was the only object the author had in view. Researches, conducted under the influence of other motives, are not likely to stand the test of a rigorous scrutiny; and some of Mr. Darwin's not unfriendly critics have produced ample evidence that the idol of speculation has been occasionally worshipped at the expense of truth.