
In construction you often have to deal with the internal measurements. For example, to determine the distance between the form panels, the value of the window or doorway. A good assistant in such cases would be sliding ruler, made of tube and metal rod with applied risk.
V. ANTIPIN
Recommend to read
GREENHOUSE-AUTOMATIC
The "greenhouse effect" can work for good — with a lack of heat in the spring or cold summer days, and evil — when the bright summer sun brings the temperature in the greenhouse to...
UNIVERSAL LEVEL
It is arranged simply: two glass tubes with a length of about 100 mm, diameter of inner hole at least 10 mm, and two lines of hose with a length of about 600 mm each. Connect it all as...