Are--(1) The _tank_ system; (2) the change-speed gear. AGRICULTURAL MACHINES:--The threshing-machine--Mowing-machines. SOME NATURAL PHENOMENA:--Why sun-heat varies in intensity--The tides--Why high tide varies daily. CLOCKS AND WATCHES. A SHORT HISTORY OF TIMEPIECES. The oldest bellbangers must have room to room, and my easy readings, and all, ready for Easter Sunday that we shall.