justness of precept, splendour of illustration, and propriety of digression. I know not whether it be pleasing to consider that he produced this piece at twenty, and never afterwards excelled it: he that delights himself with observing that such powers may be soon attained, cannot but grieve to think that life was ever after at a stand.
To mention the particular beauties of the Essay would be unprofitably tedious: but I cannot forbear to observe, that the comparison of a student's progress in the sciences with the journey of a traveller in the Alps, is perhaps the best that English poetry can shew. A simile, to be perfect, must both illustrate and ennoble the subject; must shew it to the understanding in a clearer view, and display it to the fancy with greater dignity; but either of these qualities may be sufficient to recommend it. In didactick poetry, of which the great purpose is instruction, a simile may be praised which illustrates, though it does not ennoble; in heroicks, that may be admitted which ennobles, though it does not illustrate. That it may be complete, it is required to exhibit, independently of its references, a pleasing image; for a simile is said to be a short episode.
