NO. 3 l.AMlLKY MEMOIR ON MECHANICAL ILKIIII 205 



As originally designed the wings had a curve of only 1 in IS, the main 

 front rib forming the leading edge of the wing. Later, however, it seemed de- 

 sirable to " quicken " the curve and at the same time give the wing a sharper 

 leading edge. This was accomplished by attaching to the front rib, at the points 

 where the cross-ribs joined it, properly curved wooden pieces of the form shown 

 in Plate 66, Fig. 10, over which the cloth cover of the wing was stretched. The 

 curve of the wing after the addition of this extension is shown in Plate (\C), 

 Fig. 4, and was a curve having a rise of approximately 1 in 12, with the high- 

 est point .25 from the front end. 



On account of the large size of these wings and the consequent difficulty in 

 handling them it was necessary to construct them in such a manner that they 

 could be easily taken apart, rolled up, transported to the house-boat or any 

 other poiut where they might need to be used, and then quickly reassembled. 

 After much experiment as to the best means of constructing them, the following 

 plan was devised. The cloth covering was permanently fastened to the front 

 rib, to which were attached the front extension pieces by means of small metal 

 clips secured by small wood screws. On the rear edge of the front main rib, 

 at a uniform distance of 30 inches apart, 10 small metal horns of 1-mm. tubing, 

 5 cm. long, each brazed to an independent clamping thimble, as shown in Fig. 

 9 of Plate 66, were fastened. The front end of each of the cross-ribs was 

 slightly rounded out to fit the front main rib, and in the wooden block which 

 was glued in this end of the cross-rib a hole was bored to fit these horns. Each 

 of the cross-ribs was then pushed over its proper horn and against the front 

 main rib, and the cloth covering then drawn back towai'd the rear tips of the 

 cross-ribs. In the extreme rear edge of the cloth covering a seam was made, 

 and in this was inserted the " D "-rib already described. The cloth was then 

 tightly stretched and a wood screw forced through the " D "rib and into and 

 through the metal ferrule at the tip of the cross-rib. Near the inner and outer 

 edges of the cloth covering eyelets were placed about 6 inches apart, through 

 which small cords were then inserted and tied to the end cross-ribs. The main 

 or mid-rib was then placed on top of the cross-ribs and fastened to them with 

 wood screws, and the cross-braces were then fastened on the top of the wing, as 

 shown in Plate 54. The frame of the wing was stiffened horizontally by cross 

 guy-wires which passed from each cross-rib, at the point where the mid-rib 

 crossed it, to the adjoining cross-rib, at the point where it was connected to 

 the front rib. Each of the main ribs was individually guyed, in the manner 

 clearly shown in Plate 52, in order to stiffen it in the vertical direction, the fit- 

 tings for these guy- wires being shown in detail in Figs. 11-15 of Plate 66. Fi- 

 nally, small guy-wires were run from the front end of the cross-ribs over a 

 guy-post 12 inches high at the point where the cross-rib crossed the mid-rib 

 to the rear tip of the cross-rib. These cross guy-wires were regulated in tight- 



