Once we know these heads, we will then subtract the suction head from the discharge head and the amount remaining will be the amount of head that the pump must be able to generate at the rated flow. Here is how it looks in a formula: System head = total discharge head - total suction head. H = hd - hs.
Observation Point. This well used path climbs a short, steep, wooded hillside to a viewpoint of Old Faithful and nearby features, then continues across the hill to Solitary Geyser, a bubbling pool in an open area of the forest.
A periscope is an instrument for observation over, around or through an object, obstacle or condition that prevents direct line-of-sight observation from an observer's current position. In its simplest form, it consists of an outer case with mirrors at each end set parallel to each other at a 45-degree angle. This form of periscope, with the addition of two simple lenses, served for observation purposes in the trenches during World War I. Military personnel also use periscopes in some gun turrets and in armoured vehicles.