E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
4. Blow.
A stroke, (German, bläuen, to beat or strike.)
1
At one blow. By one stroke.
2
The first blow is half the battle. Well begun is half done. Pythagoras used to
say, The beginning is half the whole. Incipe: Dimidium facti est cpisse (Ausonius). Dimidium facti, qui cpit, habet (Horace). Ce nest que le premier pas qui coûte.
3
Without striking a blow. Without coming to a contest.