If a barrel is poured in the vegetable garden or cistern in the shower — the water level in them will tell you a simple water-measuring device consisting of a Styrofoam float and stuck to his line or rod with the labels. For greater stability of water-measuring devices are required on the barrel to put the bar with the guide bushing.
Recommend to read
THE INVISIBLE WATCHMAN
Generators of low frequency oscillations, as is known, can be used as a caretaker: intermittent loud noises warn of the approach of a stranger. On the same principle and made our...
Il-4
Long-range bomber Il-4 (DB-DF) was established in 1940 Intended for bombing attacks in the deep rear of the enemy, DB-ZF from the first days of the war these planes were used to deter...