for the flat roof over the Hall at Poplar Forest.

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let the sky-light run from East to West. 16. panes long. and only the length of 2. panes wide.

groove the upper end of the pane ½ I. into the ridge bar

and let the lower end lap 1.I. on the lower bar

the ridge-bar of the sash (if in one piece) must be 2.I. sq. but if in 2. pieces they must be 1.I. by 3.I.

the lower bar or rail of the sash 4.I. wide.

the end stile of the sash 4.I. wide.

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for the frame.

lay 2. girders, 10. by 4.I. across the walls from East to West

let them be 32½ I. apart & project 3.I. beyond the walls.

tenon 2. cross trimmers into these girders 8 f–2 I from the center

the clear opening of the skylight will then be 16 f–4 I by 32½ I

the inside faces of these girders & trimmers must be planed.

on the North & South sides of these girders lap on guttur joists dovetail

these guttur joists must project over the wall 2.I.

they are 10. by 8.I. admitting gutturs 4.I. wide, & 2.I. margin.

they will be 291⁄7 I. from center to center.

then	on these 2. girders lay 2. others 4 by 6 I.
	on these upper girders lap the ridge-joists, dove-tail, letting them project 3.I. over the wall.

slop both ridge & guttur joists from end to end 6.I.

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from each corner of the skylight to the corresponding corner of the wall, lay on a hip-ridge-rafter, and from these hips & the trimmers lay rafters towards East & West. on the North & South ends the rooflets are to be.

the moulding which masks the ends of the rooflets is to be nailed to the ends of the ridge joists, which projecting 1.I. more than the guttur joists, leaves space for the water to pass off.