Book V. SCIENTIFIC OPERATIONS. 533 



pulley (c, c), over which a rope is passed from the ring or end of the horizontal pole, by 

 which it is easily raised or lowered to suit the given height of the stack. A cloth being 

 now thrown over the horizontal pole, and its lower margins loaded with weights, a com- 

 plete roof is formed and neatly fitted to the stack, whether it be high or low, wide or 

 narrow ; the eaves being always adjusted to the wall plate, or upper part of the stem of 

 the stack ; thus effectually shooting oft' rain water, while the internal moisture or steam 

 escapes freely at either end as the wind may happen to blow. This contrivance is readily 

 put up or taken away ; the poles being light, are easily moved from stack to stack, or laid 

 up for another season, and the wheels are readily removed or returned to their axles. 

 On the whole, it answers as a good substitute for the improved construction brought 

 into use by Sir Joseph Banks, and is much less expensive. This construction, instead of 

 the ring running on the poles, has blocks and tackle (c, c), and instead of weights to dis- 

 tend the cloth, ropes (</, d) are used to tighten it and keep it detached from the sides of 

 the stack, so as to admit a more free circulation of air. 



3289. si stacking stage (Jig. 520.), or scaffold, has been contrived for finishing the 



upper parts of high stacks, but it can seldom be requi- 

 site when a judicious size of stack is adopted. This 

 stage, which consists of a frame (a) and a movable 

 platform (6), easily understood and constructed, is set 

 against the stack, when it becomes so high that it is 

 inconvenient to pitch on to it from the cross plank of a 

 waggon. The platform is commonly fixed by means 

 of the chain pins and holes, about fourteen feet from 

 the ground, which is about the height of a waggon 

 load of hay. Were it fixed lower, it would be of no 

 use ; and were it fixed much higher, it would be found 



too high for a man to pitch on to when the waggon should have become nearly empty. 



3290. The term housing is chiefly applied to crops of the root kind, as potatoes, 

 carrots, turnips, &c. Potatoes being gathered in dry weather are preserved by being 

 laid up in heaps, secured from rain and frost more particularly, and from the weather 

 generally, whether dry, moist, cold, or hot. The mode of doing this in some places is 

 to form them into heaps on the surface of the soil, covering them with a thick layer of 

 straw, and on that another of earth. Sometimes also, where the soil is dry, they are 

 buried in pits and similarly covered ; but, for common agricultural purposes, by much 

 the best mode is to lay them up in a house, securing them from all extremes of weather 

 by a covering of straw. By this mode they are much more easily got at when a portion 

 is wanted, than by any other in use. 



3291 . In housing carrots, and Sivedish or yellow turnips, the same modes may be adopted 

 as for potatoes ; but in housing white turnips, as they are apt to rot when heaped up, the 

 best mode is to spread them thinly on any surface covered from the rain, but freely ex- 

 posed to the circulation of air. This mode, it must be evident, can only be adopted to a 

 limited extent, and, indeed, is only resorted to as a precautionary measure during winter, 

 when frosts, snows, or continued rains, might interrupt the lifting and carting from .the 

 fields of the usual supplies for feeding stock. 



3292. Various modes of housing and preserving these and other roots, will be treated of 

 as each particular crop comes into notice in a succeeding Book (VI.). 



Chap. III. 



Scientific Operations, and Operations of Order and general Management. 



3293. All the operations which have hitherto been described require to be practically 

 known to every farm servant or operative agriculturist ; the few about to be described 

 belong more particularly to the superintendent or master : they may be arranged as 

 scientific operations, and operations of order and management. 



Sect. I. Scientific Operations required of the Agriculturist. 



3294. The scientific operations required of the agriculturist are chiefly the measuring 

 surfaces, measuring solids, taking the levels of surfaces, dividing lands ; and valuing lands, 

 timber, leases, and farming stock. A knowledge of the more common practices of sur- 

 veying, measuring, and the calculation of annuities, may be considered as essential to every 

 agriculturist, whether farmer, land agent, or proprietor, who is desirous of having clear 

 ideas on the subject of letting labour, hiring or -letting farms, or purchasing estates. 

 Such knowledge is not to be expected in detail in this work, but must be procured from 

 the ordinary school and annuity books, and is indeed implied in a regular education. 



Mm 3 



