GENERAL ECONOMY OF THE FARM. 



289 



IV. GATES. 



ANOTHER point to be considered in relation to the fence is 

 the gate, which may be regarded as a moveable portion. The 

 properties of a good gate are that it shall combine with light- 

 ness the necessary strength, so that an equal quantity of mate- 

 rials shall produce the strongest gate. The absolute strength 

 of materials depends on their hardness and tenacity. A neat 

 and substantial gate, sufficient for all necessary purposes, may 

 consist of a set of horizontal bars, firmly bound together, and 

 placed at such distances as to prevent the passage of animals. 



The following figure represents a gate with five horizontal 

 bars, well secured and rendered firm by a diagonal bar, pro- 

 jecting from the lower to the upper corner, with an upright 

 brace in the centre, but on the opposite side. The following 

 description of an excellent gate, but of simple and cheap con- 

 struction, is by Professor Low. 



"The gate may be hung on two hinges or the heel of the gate may rest in 

 a socket placed in the ground. The bars, by tapering towards the fore-part, 

 diminish the tendency of that part to sink. When a gate sinks at the head, it 

 may be considered as a bended lever, of which the fulcrum is at B, the power at 

 C, and the weight the centre of gravity of the gate, which, in case of its being 

 of uniform materials, will be represented on the lower bar at A. Hence, by 

 increasing the length of B C in proportion to B A, the power of the hinge at 

 C to support the weight of the gate is increased. This power is further in- 

 creased, when the gate is made heavier at its posterior part, so as to bring the 

 centre of gravity nearer to B. In practice, therefore, the hinges should be kept 

 at as great a distance from each other as possible, and the gate should be made 

 light towards its anterior part." 



In the figure, five horizontal and two upright bars at the ex- 

 tremities are shown into these two outer upright bars, the 

 horizontal bars are secured firmly by morticing. The diagonal 

 brace from the higher to the lower corner, consists of a plank 

 of suitable dimensions. The horizontal bars taper from the 

 hinderpart to the forepart. The length of the gate may be 

 nine feet, the height over the horizontal bars four feet, the 

 lower bar standing about six inches from the ground. The 

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