Launch the clamp screw with the instrument, keep the instrument in the best hand, and take care of it to the tripod by rotating only the decrease element with the remaining hand. Tighten the screws on the instrument firmly. An isohyet or isohyetal line (from Historical Greek ὑετός (huetos) 'rain') https://contour-survey-in-banglad38384.blogdun.com/32829184/the-smart-trick-of-contour-survey-that-nobody-is-discussing