178 CATALOGUK. PHILOSOPHY AND ARTS, PEACTICAL MECHANICS. 



displacement should never exceed the limits of the abut- 

 ments themselves. 



Supposing the pressure of the materials vertical only, the 

 curve may be constructed mechanically without difficulty^ 

 by making the centre of each portion of it at a distance be- 

 low the arc which is inversely as the distance of the arc 

 from the road. In the case of z horizontal road, the great- 

 est curvature will be where this distance is a mean propor- 

 tional between the radius of curvature at the vertex and the 

 depth of the materials at the same point. 



Carpentry in General. 



Moxon's mechanic exercises. 



Account, Ph. cr. 1677. XII. 967. 1006. 



The three first numbers treat of smith's _work, the three 

 next of joiner's work. 



Houbo Alt du m^nuisier. f. Paris. Ace. A. 

 P. 1769. H, 124. 1770. H. 111. 



*Fuss on the strains of framed carpentry. A. 

 Petr. 1778. II. i. 194. 



E. M. A. I. Art. *Charpentier. IV. Art. M^- 

 nuiserie. 



Pain's practical house carpenter. 4. Lend. 



P. Nicholson's carpenter's new guide. 4. 

 London. 



P. Nicholson's carpenter's and joiner's assist- 

 ant. 4. Lond. 1797. R. I. 



Rohison. Enc. Br. Suppl. Art. Carpentry. 



Ilassenfratz Art de la charpenterie. 

 Approved by the Institute. 



Beams and Floors. 



Morveau on increasing the strength of beams. 

 Roz. IV. 157. 



Panseron and Bonnin on floors. R02.XXXV. 

 211. 



Upton's barn floor. S. A. XIV. 305. Repert. 

 VI. 111. 



Wilson's patent for combining timbers. Re- 

 perm IX. 100. 



Smart's patent masts and beams. Repert. 



XIV. 17. 

 Woart's mode of securing decayed beams. 



S. A. XX. 258. Nich. VI. 120. Repert. 



ii. II. 346. 



Wooden Bridges and Centres. 



Perrault's wooden bridge of a single arch. 



Mach. A. I. 59. 

 Perrault's drawbridge. Mach. A. II. 51. 

 Hebert's turning bridge. Mach. A. II. 68. 

 A wooden bridge. Ph. tr. 1684. XIV. 7 14. 

 Wooden bridges, drawbridges, centres, a 



l^ridge of ropes. Leup. Th. Pontif. 

 Pilot on the strength of centres. A. P. 1726. 



216. H. 65. 

 Gallon's faUing drawbridge. A. P. 1733. H. 



120. 

 Meyzeray's model of a bridge of ropes. A. P. 



1748. H. 120. 

 Emerson's mechanics, f. 212. 

 Perronet on the centres of bridges. A. P. 



1773. 33. H. 72. 

 Perronet sur les ponts. 

 Drawbridge. Behdor. Arch. Hydr. II. ii. pi, 



53. 

 Turning bridge. Belidor. Arch. Hydr. II. ii. 



pi. 54. 53. Enc. Br. Art. Drawbridge. 

 Robison. Enc. Br. Suppl. Art. Arch, Car- 

 pentry, Centre. 

 Plans of Grubenmann's bridge at SchaflT- 



hausen. R.I. 

 A wooden bridge. Person Recueil. PI. 10, 



Roofs. 



Couplet on roofs. A. P. 1731. 69. H. 62. 

 Salimbeni on roofs inclined one way. See. 



-Ital.IV.249. 

 Robison. Enc. Br. Art. Roof. 



