3S6 Memorandum regarding Si/r{a7i or Cylinder Hoofs, [ApftiL 



so many lofty and wide doors, that the solid parts were very slight, yet 

 the thickness of these walls, li feet have been found to answer per- 

 fectly. They were strengthened however by the Ionic-pilasters inside 

 and out, and the 10 feet cylinder arch of the verandah abutted against 

 the larger one, and thus added to the stability. In the smaller arches 

 of 17, 16, and 15 feet, the walls were purposely tried of pise, brick, 

 and mud, and a composition of both ; they were of various heights, but 

 generally about 10 feet and I2 feet thick only, the upper foot, or foot 

 and a half being built with brick in chunam. The pisd at Bangalore 

 was found to be extremely hard, but situated as was my building close 

 to water, I was enabled to build cheaper with brick, therefore that 

 mode was relinquished. 



The supporting iron hooks for chandeliers, &c. were fitted into blunt 

 wedge-shaped blocks of wood, which were built into the solid brick 

 and chunam binders as key stones, and perfectly surrounded with chu- 

 nam and masonry. 



Memorandum of the comparativk weight of the Cylinder and 

 Tiled Roofs. 



{From actual observation and experiment). 

 Cylinders. 



4 cylinders about 10 inches long— larger diameter 5 inches— smaller 

 diameter 4|— were found to cover 9? inches x 9| inches when prO' 

 perly placed. 



"Weight of the same 7-lbs. 



Now adding. 5 -bis. 



For the weight of chunam between the cylinders 

 and for the plastering on the top and bottom of 

 the four cylinders, then the total weight for a 



space, 9i inches by 9| inches * 12*-Ibs. 



(The chunam is overrated). 

 The tiles were picked and the lightest as well as the best that 

 could be procured, while no selection was made for the cylinders. 

 The flat tiles were not taken into calculation as both roofs require an 

 equal number, unless two and three coatings of these be given to the 

 arched roof, in which case as tiles are much increased in weight by 

 rain, while the cylinder roof is not so effected, the ultimate strains 

 will be even then much alike. The timber, nails, &c. of the tiled roof 

 are all in excess, and a cylinder roof once properly laid presents much 

 less resistance to the wind, and will seldom or never require repair. 



