Nor can we say how great may be its influence, when it becomes universal,--when it has been inherited by many generations,--when it is freed from the trammels of superstition and rightly adapted to the wants and capacities of different classes of men and women.

Neither do we know how much more the co-operation of minds or of hands may be capable of accomplishing, whether in labour or in study.

The resources of the natural sciences are not half-developed as yet; the soil of the earth, instead of growing more barren, may become many times more fertile than hitherto; the uses of machinery far greater, and also more minute than at present.

New secrets of physiology may be revealed, deeply affecting human nature in its innermost recesses.

The standard of health may be raised and the lives of men prolonged by sanitary and medical knowledge.