Analysis of The Last Lap

How do we know, by the bank-high river,
Where the mired and sulky oxen wait,
And it looks as though we might wait for ever,
How do we know that the floods abate?
There is no change in the current's brawling--
Louder and harsher the freshet scolds;
Yet we can feel she is falling, falling
And the more she threatens the less she holds,
Down to the drift, with no word spoken,
The wheel-chained wagons slither and slue....
Achtung! The back of the worst is broken!
And--lash your leaders!--we're through--we're through!

How do we know, when the port-fog holds us
Moored and helpless, a mile from the pier,
And the week-long summer smother enfolds us--
How do we know it is going to clear?
There is no break in the blindfold weather,
But, one and another, about the bay,
The unseen capstans clink together,
Getting ready to up and away.
A pennon whimpers--the breeze has found us--
A headsail jumps through the thinning haze.
The whole hull follows, till--broad around us--
The clean-swept ocean says: "Go your ways!"

How do we know, when the long fight rages,
On the old, stale front that we cannot shake,
And it looks as though we were locked for ages,
How do we know they are going to break?
There is no lull in the level firing,
Nothing has shifted except the sun.
Yet we can feel they are tiring, tiring--
Yet we can tell they are ripe to run.
Something wavers, and, while we wonder,
Their centre-trenches are emptying out,
And, before their useless flanks go under,
Our guns have pounded retreat to rout!