Laudator Temporis Acti

The Yale Edition of the Works of Samuel Johnson, Volume I: Diaries, Prayers, and Annals, ed. E.L. McAdam, Jr. (New Haven: Yale University Press, 1958), p. 278 (October 12, 1777):

Brachia satis setosa paulum a carpo rasi, ut notum sit quantum temporis pilos restituat.

McAdam ad loc.:

On the twelfth Johnson shaved his hairy arms enough "to see how much time would restore the hairs," a rather extreme example of his intellectual curiosity.

Id., p. 297 (August 7, 1779):

Partem brachii dextri carpo proximam et cutem pectoris circa mamillam dextram rasi, ut notum fieret quanto temporis pili renovarentur.

McAdam's note (pp. 297-298):

On 7 August Johnson made an experiment similar to the one he had made on 12 October 1778 [sic, read 1777]: he shaved part of his right arm above the wrist and the hair around his right breast to see how long it would take to grow again. Perhaps he had forgotten to keep track of his October experiment, or thought that in summer the hair would grow faster. The sentence was printed by Boswell from a lost diary (Life, III.398 n.3).

Bowswell's comment:

My readers will not be displeased at being told every slight circumstance of the manner in which Dr. Johnson contrived to amuse his solitary hours. He sometimes employed himself in chemistry, sometimes in watering and pruning a vine, sometimes in small experiments, at which those who may smile, should recollect that there are moments which admit of being soothed only by trifles.