water from unpiped sources

the meanders of an old river, or of the veins and arteries in the body

The postventricular atrial refractory period (PVARP), for example, becomes the postatrial ventricular refractory period, ventricular sensing becomes atrial sensing, and the maximum tracking rate serves as a reference rate in defining input requirements for the maximum length of the adjustable AV delay.

The departments were the bricks from which the edifice of the nation was to be constructed.