Gibb, belated agreement that your D & T must be from '27, not '06, for most all the reasons you give.

It's also useful to see the publisher explicitly dating the first edition to 1887. When it appeared it was undated, and though 1887 was always the most likely date, this confirms it.

Acc. to WorldCat, ed. 1 has 48pp., ed. 2, 78pp., ed. 3, 95pp., and the "Revised Edition," 97pp.