Your favor of the 4th. inst. came to hand some days ago; but as the question about the sashes for the S.E. portico required attention & a recurrence to my papers, I have not had time to take it up till this moment. there are 5. arches to the Piazza, the measures of which you have taken. besides the sashes, they are to have Venetian blinds of a particular construction, now in hand here, under my own eye. according to the plan on which I have proceeded, each sash must have 2. square sashes, to slide up with leads in the common way each sash 3. panes high & 5 panes wide, the panes 11½ I. by 15. I. the semicircular sash [GRAPHIC IN MANUSCRIPT] above these must have it’s base divided into 5. parts corresponding with the upright bars in the lower sashes, in the manner represented in the margin. because each semicircular bar should appear to spring from the upright one below it, & be only a continuation of that upright one bending round & meeting it’s corresponding upright on the other side. the 2. lower sashes will be 8. f. high when put together & lapped on one another in the middle, and they will be 5. f. 2 I. wide from out to out, including the depth of the 2. grooves in which they run on each side. I took these measures with great accuracy, and as the rest of the work is doing on the same measures, I wish your sashes to conform to them. if your sashes lap 1. I. at the middle, then each will be 4. f. ½ I. high and 5. f. 2. I. wide, out to out.

I now inclose you an order on messrs. Gibson & Jefferson for 100.D. according to your desire. Accept my best wishes.