Henry Watson Fowler, The King's English (1906)
“ Observance is obedience, compliance, &c. The Oxford Dictionary recognizes observance in the sense of watching, but gives no authority for it later than 1732 except another passage from Ruskin; the natural conclusion is that he accidentally failed to recognize a valuable differentiation long arrived at. It is physical science, and experience, that man ought to consult in religion, morals, legislature, as well as in knowledge and the arts.—Morley. ”
