31G 



Third layer clay 

 with one fourth 

 brick duft and 

 one fourth fine 

 land 6 or S 

 inches thick. 



Hbufes thus 

 built cod 6 

 franks for the 

 cubic fathom. 



May be made 

 with many flo- 

 ras. 



An houfeof this 

 fort 430 years 

 built feemed 

 <juite-frefh. 



ON STEAM-ENGINES. 



and joifh, and it is confolidaled by light blows of wooden 

 trowels, until it is perfectly dry. When the clay forms cracks 

 in drying they arc clofed by other clay prepared for filling up 

 thefe chinks to the bottoms. 



The fecond layer when perfectly dry, and free from cracks, 

 is covered wilh a third layer; which iscompofed of pulverized 

 clay mixed with a fourth of brick duft, parted through a clofe 

 fieve, and with a fourth of fine fand. This mixture is worked 

 up in a trough like mortar ; it is ufed as foon as prepared, and 

 is then fpread out equally over (he whole terrace iix or eight 

 inches thick ; this layer is consolidated in the fame manner as 

 the others, and this labour is continued till it is perfectly dry ; 

 and then the argrnnace is finilhed. This terrace is ftrong, and has 

 fuch tenacity that the molt violent rains cannot penetrate it. 

 " A building of this fpecies cofls in India but fix francs (five 

 fbilitngs) for the cubic fathom and is entirely performed by 

 mafons. In Frahce it would coft three limes as much (and 

 fomething more in England) on account of the greater expence 

 of labour and fuel. 



Houfes may be built in this manner of any height required, 

 and of as many {lories as are thought fit ; I have feen fome 

 that had but one ground floor; but I have alfo feen others that 

 were elevated two fiories above the ground floor. One of this 

 laft fort, filuated on the banks -of the Gemna in the province of 

 Alabad, was built above 430 years, and the walls, and 

 the whole of the building looked as frefh as if they were new. 



IV. 



Account of fame new Improvements on Steam- Engines. By Mr. 

 Arthur Woolf. 



(Concluded from page 296.) 



"I 



in (ream-en- 

 gines 



^ have found out and invented a contrivance, bv which 

 improvements the temperature of the fleam vetlel or working cylinder of a 

 fleam-engine, or of the fleam veflels or cylinders where more 

 than one are ufed, may be raifed to any required temperature, 

 without admitting fleam from the boiler into any furrounding 

 receptacle, whether known by the name of a fleam cafe, or 

 by any other denomination. That is to fay, inftead of admitting 



fteara, 



