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refracted by passing through its humours, and impinging on itsbottom, may form a perfect image of an external object, as we seeis mechanically done in the camera obscura. We can compre-hend how the impulse of a wave of air on the tympanum of theear may there excite a vibratory motion, as we see is done by astick impinging the parchment of a drum; but why the man hasa perception of sound which the drum has not, or an idea offigure depicted on the choroides or retina of the eye, (which everof them be the seat of vision,) which the camera has not; in otherwords, how perception is excited from material impulse, mustever, I think, exceed the apprehension of human intellect. Thedifficulty is not removed by introducing an immaterial substance,since, as such, we must conceive it to be incapable of either givingor receiving material impulse; but our inability of apprehensionought never to be urged as an argument against the possibility ofexistence, since we are certain that God is an immaterial sub-stance, and the primary Author of all material impulse existing inthe universe.

“ Wishing success to your lectures,

“ I remain, your faithful and obliged servant,

R. Landaff.”

The following is a Letter to one of my oldest and most re-spected friends, Mr. Harrison, who whilst in the House of Com­ mons acquired and deserved the esteem of all honest and inde-pendent men, and who had written to me on the subject then inagitation, the imprisonment of Sir Francis Burdett : —