. An encyclopædia of agriculture : comprising the theory and practice of the valuation, transfer, laying out, improvement, and management of landed property, and of the cultivation and economy of the animal and vegetable productions of agriculture. ng (2d 6970), and Gorries in the Gard. Mag.(voL ii. p. 9.), we shall here confine our-selves to the invention of Mr. Rogers. 4076. Rogerss dendrometer (Jig. 600)consists of a tripod stand, and a machinefor taking angles horizontally as well asvertically. An upright stem arises fromthe top plate, at the end of which is aball, with a hole perfo
. An encyclopædia of agriculture : comprising the theory and practice of the valuation, transfer, laying out, improvement, and management of landed property, and of the cultivation and economy of the animal and vegetable productions of agriculture. ng (2d 6970), and Gorries in the Gard. Mag.(voL ii. p. 9.), we shall here confine our-selves to the invention of Mr. Rogers. 4076. Rogerss dendrometer (Jig. 600)consists of a tripod stand, and a machinefor taking angles horizontally as well asvertically. An upright stem arises fromthe top plate, at the end of which is aball, with a hole perforated through it, toreceive the horizontal stem of the in-strument ; b c may be called the baselimb of the instrument, which is to beplaced in a truly horizontal position,and adjusted by the suspended level (rf).The limb (e) rises on a joint at r, andslides upon a vertical arch (J) which isgraduated. At the joint (c) there is aneye-piece, through which the surveyorlooks along the side of the bar (6) to asmall point, or rising edge, at the end ofthe bar ; the part of the tree cut by thisline of observation will, if the instru-ment is properly adjusted, be perfectlyhorizontal with the eye-piece. An ej e-piece is also placed at c, on the upper. PRACTICE OF AGRICULTURE. Part III. ?Ids of tin rising linii), for tin purpose of looking along tin. iiniii to .1 poinl or rising edge (e) in itsextremity. The surveyor elevate* this limb, until that part of the trie intended t be noticed ia exactlyrut by the line • I ion, and the angle subtended between thai and the horizontal is shown upon the vertical arch [f] It i- here to be remarked, that the graduations upon the arch ^ /) are not anglesol altitude, bul marks or graduations answering to feel and inches of a tangent line, extending from thehorizontal point upwards, taken at a given dl I mi from the tree; consequently, then are two or moreof divisions, answering to the sevur feet will be sufficient. The hori
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Keywords: ., bookcentury1800, bookdecade1870, bookpublisherlondo, bookyear1871
