6 
A Catalogue oj 
\ 
Surveying Inftruments, &c. 
t 
31 1PJLAIN tables, with an index and fights, 
JL whereby the draught or plan is taken on 
the fpot, without any future protra&ion, hav¬ 
ing a compafs fitted to one of its fides, and 
the whole fixed upon a ball foeket, with a 
three legg’d ftaff, upon which it may be 
turn’d round, or fatten'd with a fcrew, as 
oceafion requires. 
32 Beighton’s plain tables, with an index, whereby 
the line of fights is always over the center of 
the table, the ftation lines drawn parallel to 
thole meafured on the land ; and the table fet 
horizontal by a fpirit level. In this table the 
papers being fquare, are readily laid together 
and compole the whole furvey in one view. 
Theodolites for meafuring angles, diftan- 
ces, altitudes, &c. Thofe inftruments are 
made various ways, fome being more fimple 
and portable, others more accurate and expe¬ 
ditious. 
33 The plain theodolite, which confifts of four 
plain fights, two fattened to the limb, and 
two on the ends of the index, with a com¬ 
pafs on the index plate, divided into degrees, 
and the limb fubdivided into minutes by a 
nonius divifion, the whole fitted on a ball 
and foeket, and that placed upon a three- 
leggkl ftaff. 
34 Theodolites, with all the above particulars, 
and the addition of a telelcope. 
35 Theodolites of the lateft improvement, being 
the moft accurate inftrument yet invented for 
furveying land, which may be ill truly hori¬ 
zontal. 
