Rudimentary treatise on the erection of dwelling-houses : illustrated by a perspective view, plans, elevations, and sections of a pair of semi-detached villas with the specification, quantities, and estimates and every requisite detail, in sequence, for their construction and finishing / by . ngers andcan be turned round as delicately as they require to bemoved for drawing very minute circles. The adjoining figures represent the pencil bow assuited for describing: arcs of differentradii. Fie:. 1 &• is a construction adapted for describing arcs of a ra-dius intermediate between those
Rudimentary treatise on the erection of dwelling-houses : illustrated by a perspective view, plans, elevations, and sections of a pair of semi-detached villas with the specification, quantities, and estimates and every requisite detail, in sequence, for their construction and finishing / by . ngers andcan be turned round as delicately as they require to bemoved for drawing very minute circles. The adjoining figures represent the pencil bow assuited for describing: arcs of differentradii. Fie:. 1 &• is a construction adapted for describing arcs of a ra-dius intermediate between those de-scribed by the above-named com-passes, and those capable of beingproduced by the bows represented byFig. 2. In Fig. 1 the pencil point b, andthe centre point f, can be opened aconsiderable width by the joint A,whilst in the other construction,Fig. 2, the corresponding points eand g are limited in their opening,the two blades carrying the points,being formed out of one solid pieceof steel, and tempered so as to form aspring at the upper part corresponding with the joint ain Fig. 1. The spring of the two blades is then kept inobedience by an adjusting screw d, by which the twopoints may be set to any required degree of minuteness,and very small circles may be described with a precision E. 74 ERECTION OF DWELLING-HOUSES. that could not be expected or scarcely attempted bythe construction of Fig. 1. The pen bows are represented in the annexed engrav-ing ; their construction is similar to the pencil bowslast described. In the pen point ofFig. 1, there is a second joint just belowletter a, by which, when the instrumentis open for use, the pen may be set per-pendicular, or nearly so, to the paper,which is essential in the use of the draw-ing pen. This is a corresponding con-trivance with that noticed in describingthe compasses with movable points. InFig. 2, b shows the spring blades carry-ing the points g and d} and c, the adjust-ing screw, to set these points to the re-quired ra
Size: 945px × 2645px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, booksubjectarchitecturedomestic
