Definition of "topmost"

Well! well! [sic] cried I, as the coachman turn’d in at the gates, I find I shall do very well : and by the time he had wheel’d round the court, and brought me up to the door, I found myself so much the better for my own lecture, that I neither ascended the steps like a victim to justice, who was to part with life upon the topmost, nor did I mount them with a skip and a couple of strides, as I do when I fly up, Eliza! to thee, to meet it.

1768, Mr. Yorick, A Sentimental Journey‎, page 114

When he has defended THE TRIPLE FORTRESS of Religion, Morality, and Literature, from it's[sic] foundation to the topmost battlements, must he be left on the field without the common honours of a common soldier?

1798, Thomas James Mathias, A Translation of the passages from Greek, Latin, Italian, and French Writers, quoted in the Prefaces and Notes to the Pursuits of Literature; A poem, in Four Dialogues‎, London T. Becket, page IX (60)

Does it narrow our notions of life's wonder and dignity to peer into the abyss of being, and learn something of the marvellous laws of things — to discover the same mysterious Something in a snow-flake, in the scent of a rose, in the topmost star of unascended heaven," and in some prayer or aspiration in the soul of man?

1800, William Hurrell Mallock, The New Republic: Or, Culture, Faith, and Philosophy in an English Country House‎, London Chatto and Windus, page 220

While he worked to ply fingers back apart more than not, Kaiselan practised his crouch exploring the outpost's more topmost levels.

2015, Seth Giolle, The Cane Stories‎