Calendar: 1874-1875 Page 579

APPLIED SCIENCES 579 SECOND YEAR Given the theodolite Describe the usual adjustments viz adjustment for the Parallax Line of Collimation and the level attached to the telescope base line of mile in length was measured on plain of 000 feet above the level of the sea Give its true value at the sea's level Explain the vernier and its use An isosceles triangle contains 400 acres the angle at the vertex is 40 what will be the length of the two sides to mark off 200 acres In an isosceles triangle the base measures 500 yards and the angles at the base equalling 30 degrees each Required the area The variation of the needle is 15 300 Required the true bearings of the following 23 18 40 35 Ν 14 40 18 N2S 15 When levels are taken by the theodolite what corrections have to be allowed for Wi is the repetition of the readings of the theodolite advisable FIRST YEAR Describe the Circumferentor and state in what cases it would be advisable to use it in preference to any other instru- ment Describe the theodolite and explain how an angle is repeated In measuring base line give instances of the usual methods employed without calling into use any angular instru- ment for passing obstacles such as trees houses ponds or rivers first where you can see across secondly where you cannot What method would you employ to ir sure accuracy when chaining base line over hilly ground Convert 42 acres poles of Lancashire measure into Derbyshire and Statute acres