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92 Foot distance froin D you will have an Off set to the Right of 5 Foot, and the whole diftance between D and E will be found to be ico Foot; then placing your Instruat E, cause a Man to stand at D, and another at F, and lay the Index upon the Diameter, and turn your Inftrument about till you-efpie the Man at D; there make faft your Inftrument, and direct your Sights to É, and note the degrees cut by the Index, which will be found to'be 210 deg. then with your Rod measure the Off-set to the Right, and it will be found to be. 7 Foot; then witli yoor Chain measure to "wards F, and at 9 Foot distance from E, you will hale' a Street both to the Righe and Left; the Oft let at the same time will be found to be to the Right 7 Foot, and to' the Left 12 Foot; ftill mä'uring to wards F, you will find that ar 70 Foot di. ftance from E, your last Stations, you will find the Off set to the Left to be 7 Foot,

] and the Off fet co the Right to be 7 Foot, the whole diftance between Ehod F is 81 Foot, then placing your Instrument at F, causé a Man to ftand at A, and another to

ftand at E, the place where you last had a " Station, then 'laying your Index upon the Diameter of your Dstrument, turn the fama about until through the Sights you efpie the Man at Ethere make your Inftrumens faft, and direct your Sights to the Man

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that stands at A, ard you will find the Index will cut 74 deg. and. 30 min. then with your

Chain measure towards A, and at 8 Foot distance from F the Off-Set to the Right will be found to be 's Foot, and to the Left 7 Foot; then measuring on towards å, at 67 Foot distance from F, you will have a Street both to the Right and Left; and still measurirg on towards A, at

123 Foot distance from F, the Off-set to the Right is 4 Foot, and to the Lofts Foot, and the whole distance between F and A is 129 Foot, then have you done with the Observations in the High Streets.

Nete, You are to set down all your Observations as you go along in your FieldBock or Eye.draught, which is best. may make an Eye.draught thus; Firft go along the place that you intend to take a Plot of, and draw Lines to imitate the fame, with crofs Streets if there be any, noting your Sations therein by this Maik 2, reto ting at every Station the Angles observed, and the Off-set on either side the Line, as you find it to be when you take thein, and the L'ngth of the Lines between Station and Siation, and by this means when you come to protract your Work, you will have a repreCentation of all the work that you have

taken ; but if you set down all your Obferrations in your Field Book, it will be neceffary to let them down in manner and form



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The Table of Observations taken when you went about the

High Streets.

Of-Sets. Station. Angles. Dift.

Rif L. 2. m.' Feet.

Feet Feet IOA 95 30 at

6 from A 007 at

47 from A

la Street R.XL. 10
92 from A

이 S
100 from A

12 00 2 B 140 00 100 from A H 8 at

61 from B aStreet

to the R. & L. 99 1 20. from B


8 at

127 from B 3.0 C100 00127*from B:

8 00 8 from C

9 oo oo 64 from C


4 at 75-- from C

12) oo OD 100 00 75 from C. 4

41 from Da Streeth

to the R. &LISCO at9.3 froin D

CO 7 SE 210 DO 1oo from D at

9 la Street R. & L. 7 12 at70 from E

77 6 F74 30 83 from E

8 j rom F

7 at

67 a Street R. &L.
00.00 123 from F

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Having thus taken your High Streets, you ma in the like manner proceed with the other small Streets and Lines, with several Boughs and Breaches, noting down in your Eye-draught or Field-Book against every one of them, the Off-sets fo, the Right or Left, according as you find them on either side of your Chain. Note,,

That when you take your maio Streeis, it will he convenient as often as you come agaift any cross Street to take a Sight down it, and note the place or mark that you take to, and the place of standing when you take your Sight to any Mark that is in the cross Streets in your Eye-draught with this Mark o, and so by that means you

will know where to place your Inftrument when you begin to take the cross Streets; your high Streets and your cross Streets being thus taken, in the next place you are to take the measure of the Houses to the Front, and likewise the depths of every one of them, and with your Rod or Bevil take the Plots of your Courts and Alleys, fift by drawingan Eye-draught of them, setting upon every Break or Return thereof the measure you took with your Rod, and in so doing, you will find it no hard matter to protract the saine after you have protracted both sides of every Street ; for you will have the RepreTentation of every Coust and Alley in its proper place.

300 TSI : D p! Tk 10"

C Η Α Ρ. ΙΙ. .
How to protract ori lay down any

Observation taken arcording to the
Directions of the last Chapter.

Vrst, having provided your felf of good

Paper or Velam to protract it upon,draw & Line at length to represent the Line AF first, then laying the Center of your Protractor upon the Poini, trwn your Pratractor about until the Lige AB thereof lya directly on the Line AF, then finding by your Field Book or Eye-draught that the Angle-observed at A, was. 95 deg. and

30 min. against 95 drg. 30 min. of your Prom tractor make a Mark', and draw. thé Line AB at lengh'; then finding also that the length of A B was too foot, take 100 froin off ypúr Scale of equal Parts, and place it from A to B ; then placing the Center ol your Protractor on the point B, turn your Protractor about until the Line AB thereof lie directly upon the Line A B laft drawn then finding that the Angle observed at B., was 140 deg. against 140 of your Protractor make a Mark with your protracting pin;



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