56 Mr. White on Calcareous Cements. 



compression being continued until it was entirely destroyed with 

 92,160 lbs. or 41 tons, 320lbs. 



Second Trial, Pier (B) Pozzolano three parts, lime one part. — 

 Section one hundred and eighty inches superficial, this being over- 

 laid with sand at] top, the same escaped compression, so that the 

 result was uncertain. 



Third Trial, Small fresh-built pier nine inches square, Pozzo- 

 lano three parts, ground lime one part. — Compressed a very little 

 with 18,720 pounds, entirely destroyed with 24,480 lbs., section 

 eighty-one inches superficial. 



Fourth Trial, (G) Atkinson's Roman cement and sand, equal 

 measure. — Cracked on two sides with 37,440 lbs., entirely de- 

 stroyed with 80,640 lbs., section one hundred and ninety-six 

 inches superficial. 



Fifth Trial, (H) Pozzolano four parts, lime one part — Cracked 

 with 28,800 lbs., fracture increased with 48,960 lbs., entirely 

 destroyed with 51,840 lbs. 



Sixth Trial, (C) Pozzolano three parts, Dorking lime one part. — 

 Fractured one side with 31,680 lbs., fracture increased with 

 43,200 lbs. ; fracture again increased with 48,960 lbs. ; this expe- 

 riment was not pursued until the pier was entirely destroyed, &s in 

 the preceding one. 



Seventh Trial, (D) sand three parts, one part stone lime putty. — 

 Compressed on application of weights one-eighth of an inch, 

 cracked with 40,320 lbs., fractured in five places with 46,080 

 lbs., which entirely destroyed it. 



EigMi Trial, Pier of Portland stone fourteen inches by 12 inches, 

 two feet seven inches high. — A sudden fracture was produced 

 which divided the stone into two pieces in the centre of the widest 

 side with one hundred seventy-three and a half tons ; the upper end 

 of the stone was bedded in Pozzolano, which was compressed into a 

 cake of five-eighths one -fifteenth thick, in a wet state ; which cake 

 remained quite solid after the fracture of the stone. 



These trials were made in the presence of Mr. Smirke, Mr. 

 Brunei, Lieutenant-General Sir A. Bryce, Mr. T. L. Donaldson, 

 and many other gentlemen. 



