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92 Foot diftance from D you will have an Off fet to the Right of 5 Foot, and the whole diftance between D and E will be found to be 100 Foot; then placing your Inftru at E, caule a Man to ftand 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 F, and note the degrees cut by the Index, which will be found to be 210 deg. then with your Rod meafure the Off-fet to the Right, and it will be found to be 7 Foot; then with your Chain meafure towards F, and at 9 Foot diftance from E you will have a Street both to the Right and Left; the Off let at the fame time will be found to be to the Right 7 Foot, and to the Left 12 Foot; ftill meaturing towards F, you will find that at 70 Foot diftance from E, your laft Station, you will find the Off fet to the Left to be 7 Foot, and the Off fet to the P to be 7 Foot,

the whole diftance between E and F is 8r Foot, then placing your Inftrument at F, caufe a Man to ftand at A, and another to fland at E, the place where you laft had a Station, then laying your Index upon the Diameter of your Luftrument, turn the fame about until through the Sights you efpie the Man at E, there make your Inftrumens faft, and direct your Sights to the Man thas

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that ftands at A, and you will find the Index will cut 74 deg. and 30 min. then with your Chain measure towards A, and at 8 Foot diftance from F the Off-fet to the Right will be found to be 5 Foot, and to the Left 7 Foot; then measuring on towards A, at 67 Foot distance from F, you will have a Street, both to the Right and Left; and ftill meafurirg on towards A, at 123 Foot diftance from F, the Off-fet to the Right is 4 Foot, and to the Left s Foot, and the whole diftance between F and A is 129 Foot, then have you done with the Obfervations in the High Streets.

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Nate, You are to fet down all your Obfervations as you go along in your FieldBook or Eye-draught, which is beft. 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 cross Streets if there be any, noting your Stations therein by this Mark; fetting at every Station the Angles obferved, and the Off-fet on either fide the Line, as you find it to be when you take thein,and the Length of the Lines between Station and Station,and by this means when you come to protract your Work, you will have a reprefentation of all the Work that you have taken; but if you fet down all your Obfervations in your Field Book, it will be neceffary to fet them down in manner and form

The Table of Obfervations taken when you went about the High Streets.

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Having thus taken your High Streets, you may in the like manner proceed with the other fmall Streets and Lanes, with feveral Boughs and Breaches, noting down in your Eye-draught or Field-Book againft every one of them, the Off-fets to the Right or Left, according as you find them on either fide of your Chain.

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Note, That when you take your maio msi Streets, it will be convenient as often as you come againft any crofs Street to take a Sight down and note the place or mark that you take to, and the place of ftanding when you take your Sight to any Mark that is in the cross Streets in your Eye-draught with this Mark, and fo by that means you will know where to place your Inftrument when you begin to take the crofs Streets; your high Streets and your crofs Streets being thus taken, in the next place you are to take the measure of the Houles to the Front, and likewife 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, fetting upon every Break or Return thereof the measure you took with your Rod, and in fo doing, you will find it no hard matter to protract the faine after you have protracted both fides of every Street for you will have the Reprefentation of every Court and Alley in its proper place.

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a Line at length to reprefent the Line AF firft, then laying the Center of your Protractor upon the Point, turn your Protractor about until the Line AB thereof lye directly on the Line AF, then finding by your Field Book or Eye-draught that the Angle obferved at A, was 95 deg. and 30 ३० min. against 95 deg. 30 min. of your Pro tractor make a Mark, and draw the Line AB at length; then finding alfo that the length of A Bwas too foot, take 100 from off your Scale of equal Parts, and place it from A to B; then placing the Center of your Protractor on the point B, turn your Protractor about until the Line A B thereof. lie directly upon the Line A B laft drawn ; then finding that the Angle obferved at B... was 140 deg. againft 140 of your Protractors make a Mark with your protracting pin,. K 4

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