. Sun dials and roses of yesterday; garden delights which are here displayed in every truth and are moreover regarded as emblems . me by shadowesafter the most Methodical! Compendious and Perspicuous Mannercompleatly and demonstratively delivered for all Planes both byLi?ies and Numbers. The worth of this Work will be best valuedby those who alter sad wanderings have at length sate down wearied,with the obscure and toylsome Labyrinths of others. — Sciographia, or The Art of Shadoiues^ John Wells, EsguiRE^ 1635. UOTING from a mathematicaltreatise, we define dialling orgnomonics as treating of t
. Sun dials and roses of yesterday; garden delights which are here displayed in every truth and are moreover regarded as emblems . me by shadowesafter the most Methodical! Compendious and Perspicuous Mannercompleatly and demonstratively delivered for all Planes both byLi?ies and Numbers. The worth of this Work will be best valuedby those who alter sad wanderings have at length sate down wearied,with the obscure and toylsome Labyrinths of others. — Sciographia, or The Art of Shadoiues^ John Wells, EsguiRE^ 1635. UOTING from a mathematicaltreatise, we define dialling orgnomonics as treating of theconstruction of any instru-ment, portable or fixed, whichdetermines the divisions of theday by the motion of a shadowof some object on which thesuns rays fall. A short definition of differ-ent mechanical forms of sun-dials, and of a fewof the terms used in dialling, will be necessaryfor the full understanding of this chapter, and ofany rules for the construction of dials. Dials areportable and fixed. The former are described inanother chapter. The term fixed dial is appliedto any dial fastened in a permanent position. 87. 88 Sun-dials and Roses of Yesterday The dial may be horizontal or vertical, or inclining,which latter means fixed in any sloping position,fixed on any place that is not horizontal or verti-cal. A declining dial is one which does notface exactly either north, south, east, or west. Aproclining dial is one whose plane is not vertical,but leans forward at the top ; a reclining dial is theopposite, where its plane slopes backward. A refrac-tive dial uses refracted light; such are the window-dials described in another chapter. A reflective dialis one in which the time is indicated by a spot oflight thrown by a bit of mirror; such are cylindrical dial is one drawn on a cylindrical sur-face, usually a half-cylinder; these are found onlectern-shaped dials. A globe-dial, star-dial, and across-dial are in the forms indicated by their names. A quadrantal
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectsundial, bookyear1902
