Calendar: 1880-1881 Page 677

APPLIED SCIENCES 677 will be its correct measure upon the sea level the length of the degree upon the equator being taken at 69£ geographical miles It is required to lay off 200 acres from the apex of an isosceles triangle whose sides bear respectively 16 and 16 what will be the length and bearing of the base The vernier of theodolite whose graduated limb reads to 20 minutes is required to read off to 30 seconds How will you arrange it Construct rectangle to contain 150 acres so that one side shall be 20 chains longer than the other In measuring base line how would you manage where the line crossed lake or river and where it crossed home- stead or wood the continuity of the ranging and chaining upon the spot being indispensable FIRST YEAR The English unit of area is the acre which is equal to 10 square chains there are also roods in an acre and 40 rods in rood prove that the length of the chain must be 66 feet Given rectangular field wrhose adjacent sides are as 10 to and whose acreage is acres what must be the width of path all round inside to contain one half of an acre Describe the theodolite-its motions and adjustments What is meant by repeating an angle and give an example of how it is entered and dealt with in the field note- book What is the mean aiigle when the first angle is 280 24' the second angle 200 47' and the third angle 121 11' Describe the circumferentor and state generally upon what work you would use the circumferentor and upon what the theodolite What is meant by meridian line and by the variation of the needle and how would you ascertain approximately the variation of your own needle Describe the spirit level and explain the principle upon which the college level staff is constructed