II. 



IMPLEMENTS. 



HE instruments used in surveying and levelling 

 ordinary places are few and simple, such as 

 tape-line, compass, and water-level. 



The tape-line is made in lengths of fifty or 

 a hundred feet and can be wound up in a 

 circular leather case when not in use. It is made of steel 

 or linen with steel wires to prevent stretching, and divided 

 into feet, tenths of feet, or inches and quarter inches. The 

 tape-line can be used for measuring plots of ground when 

 no other instrument is convenient, the angles being taken 

 in a simple manner by setting off given lengths on the line, 

 thus 3, 4, and 5 feet will give an angle of 45. If we 

 desire to find out the distance between a given base-line 

 and some interesting object, such as a tree, a flower-bed, or 

 shrubbery, the tape-line must be held at right angles to the 

 base-line, or, in other words, the shortest distance between 

 two parallel lines should always be measured. It is also 

 important to hold the line horizontally above the surface 

 when measuring distances on broken or undulating ground. 

 Curves of walks and drives, outlines of shrubberies and 



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