gives himself up to his subject, or lays about him and buffets sceptics and gainsayers, arrests attention in spite of every other circumstance, and fixes it on that, and that alone, which excites such interest and such eagerness in his own breast! Besides, he is a logician, has a theory in support of whatever he chooses to advance, and weaves the tissue of his sophistry so close and intricate, that it is difficult not to be entangled in it, or to escape from it. "There's magic in the web." Whatever appeals to the pride of the human understanding, has a subtle charm in it. The mind is naturally pugnacious, cannot refuse a challenge of strength or skill, sturdily enters the lists and resolves to conquer, or to yield itself vanquished in the forms. This is the chief hold Dr. Chalmers had upon his hearers, and upon the readers of his "Astronomical Discourses." No one was satisfied with his arguments, no one could answer them, but every one wanted to try what he could make of them, as we try to find out a riddle. "By his so potent art," the art of laying down problematical premises, and drawing from them still more doubtful, but not impossible, conclusions, "he could bedim the noonday sun, betwixt the green sea and the azure vault set roaring war," and almost
