4 1.' 



SCIENCE OF AGRICULTURE. 



Part II. 



bottom. The stones to be broken arc laid on a circular basement, rounded at some 

 •408 depth below the surface, the foundation of which is 



prepared in the following manner : — "A stratum 

 is formed of clay, well tempered, and mixed with a 

 proportion of burnt limestone, powdered without 

 being slacked] and forge ashes beat very small. 

 When this is properly dried, a bed of sand, about 

 eighteen inches in thickness, should be laid above 

 it, and pared with common paving stones of the 

 kind used for streets : this, after being well beat 

 down, should be covered with another bed of 

 sand of the same thickness, which should be 

 paved in the same manner, and afterwards well 

 beat down. The foundation of the building 

 should be, at least, six feet below the common 

 surface ; which will allow eighteen inches for 

 the clay, thirty-six inches for the two beds of sand, and eighteen inches for the two 

 courses' of pavement. The circumference should consist entirely of hewn stone, at least 

 the uppermost three feet of it ; the stones of which should be strongly batted together 

 with iron, and secured on the outside with numerous wooden posts driven into the earth, 

 and different courses of pavement, extending at least six feet all round, carefully laid, 

 and well beat down. A floor prepared in this manner, if it is not used too soon, will 

 resist any force that can be let fall upon it. The limestone laid into it should not be 

 too small, and should have a light bedding of sand in the soil to give it stability." 

 (Farm. Mag. vol. iii.) 



2809. A stone-hewing machine to be impelled by steam has lately been invented by 

 Mr. James Milne of Edinburgh. It is said to save an immensity of manual labour, 

 and to be competent to the execution of the finest mouldings. (Scotsman, Oct. 28. 

 1829.) 



2810. Low's Machine fur raising large stones (Jig. 409.) is a powerful engine. An 



iron plug is driven into the stone, and 



409 retained there by its elasticity. The 



machine " is placed over the stone to be 

 raised, by extending the posts on each 

 side, and then the windlass is attached. 

 Of the stone to be thus raised, however 

 large it be, it is enough to see the smallest 

 part appear above the surface of the 

 ground. At this part, let a workman, 

 with a mallet, and the common steel- 

 boring chisel of masons, make a small 

 ty circular hole, about two inches deep, and 

 as peipendicular as possible. This chisel 

 should be of such a size as to make the 

 hole about a sixteenth part of an inch less in diameter than the plug itself, so that a 

 stroke or two of a hammer may be necessary to drive the iron home. When the latter 

 is thus driven an inch, more or less, into the stone, it is attached to the block, and the 

 ropes are tightened by turning the winch. Nothing more is now requisite than to set as 

 many persons as may be required to work the windlass ; and, strange as it will seem, 

 with no other fastening than this simple plug, the heaviest mass will be torn up through 

 every opposing obstacle." (Quar. Jour. Agr. vol. i. p. 208.) 



Chap. III. 



Edifices m use in Agriculture. 



*2811. A \anclij of buildings are necessary for carrying on the business of field cul- 

 ture ; the nature and construction of which must obviously be different, according to the 

 kind'of farm for which they are intended. Suitable buildings, the editor of The Farmer $ 

 Magazine observes, are scarcely less necessary to the husbandman than implements and 

 machinery ; and might, without much impropriety, be classed along with them, and 

 considered 'as one great stationary machine, operating more or less on every branch of 

 labour and produce. There is nothing which marks more decidedly the state of agricul- 

 ture in any district, than the plan and execution of these buildings. 



