178 Miscellaneous Intelligence. 



Quartz pebble in Bedfordshire gravel 70 



Ferruginous sandstone of Bedfordshire 20. 42 



Hurlock from lower chalk 10 



Chalk 3 



Granite, Scotch 110 



Flint, yellow 33. 26 



Greenstone or basalt, Quittle-Hill near Coventry ... 110 



Sandstone, soft 13. 6 



Tile fragment 20 



Gritstone, near Brixworth, Northamptonshire .... 48. 60 



Limestone, near Bradwall, Bucks 5 



Dry clay 12 



Flint, black 11. 30 



Portland stone, hard 14 



Quartz, white ... 56 



Blue pebble, like Rowley rag 105. 1 10 



Coarse limestone, near Stilton, Huntingdonshire .... 60 



Gritstone, on road near Leeds 100. 115 



Yorkshire paving stone 20 



Ketton, hard 20 



Tetternhoe 4 



Chert? from hills in Devon and Cornwall 57 



Gray wether, Hertfordshire and Wiltshire 18 



Grit of upper bed, Collymeston, near Stamford, Lin- 1 ^ 



colnshire J 



Second bed do 100 



Slate at do 50 



Stockton limestone, Warwickshire (lias) 45 



Newbold, on Avon, do 36 



Limestone of Stoke Cruerne, Northamptonshire 35 



The steady pressure, without percussion, required to crush a 

 piece of the marble weighing half an ounce, was 100 Ibs ; to crush 

 the grey flint of 1.2 oz. weight, 2000 Ibs. ; to crush the rolled 

 white quartz pebble of 2 oz. weight, 3400 Ibs. * 



A specimen of the copper slag, recommended for roads by Mr. 

 Fisher of Newgate-street, was sent by Mr. Taylor to Mr. Bevan, 

 to be tried and compared with the above. Mr. Bevan reported 

 upon it, that it was the hardest material he had met with, its num- 

 ber being 234, or above double the highest in the list. The specific 

 gravity was 4.32. A substance of such hardness, not subject to 

 decomposition by exposure to weather, and of moderate price, is 

 considered by Mr. Bevan as a most valuable material for roads of 

 great traffic and heavy loads f. 



* Vol. is., p. 164. f Phil. Mag., N. S., ix,, 317. 



