Perhaps the surest indicator of technological progress in any civilisation is the availability and the reliability of its measuring instruments. With their use, the practical technique and science achieve a two-way and productive connection. The Greeks invented numerous precision measuring instruments such as the goniometer, the odometer, etc., which enabled the development of all ancient disciplines from engineering to astronomy. Their distant travels, the exact calculation of the Earth’s diametre, the mapping of the Earth and their amazing constructions are just some results of the above.