3B2 Mr John Sang oti a Convenient Arrangement 



It is much to be regretted that there is no collection of the sepulchral 

 remains of our ancestors. Ample resources yet exist for enriching such a 

 collection were it but Commenced ; but these resources are diminishing 

 every day. Great numbers of skeletons have been found, and the bones 

 scattered, within my knowledge, during the last few years. In Ireland 

 the Royal Academy have set a laudable example in the care directed to 

 such pursuits, and much may be expected from the enlightened zeal and 

 activity of Dr Wilde and other members. How much might the Society 

 of Antiquaries have effected if their attention had been directed to these 

 researches ?^' 



On a Convenient Arrangement in Orthographic Projection. 

 By Mr John Sang, Land- Surveyor, Kirkcaldy, M.S. A. 

 With a pUite.t Communicated by the Society of Arts for 

 Scotland. 



The facility of the isometrical method of projection is de- 

 rived from the circumstances that the three axes in the di- 

 rections of the height, length, and breadth of objects, are re- 

 presented by lines having an integral proportion to one another, 

 and that the scale is applied to these, and not, as in an ordinary 

 corner projection, to those lines which merely happen to be 

 parallel to the plane of the drawing. In the isometrical pro- 

 jection, the proportion of the representations of the axis to one 

 another, is that of equality, so that the line of sight is invari- 

 able, and the draughtsman has not the power of giving more 

 or less space to the top, end, or front of the object to suit the 

 degree of development he may wish in those parts. By alter- 

 ing the position of the perspective plane, the representations 

 of the three axes may be made to have various proportions to 

 one another different from equality ; if these proportions be 

 all different from equality, and from one another in a projec- 

 tion, that projection itself will give three directions of view, 

 according as the greatest line is made to represent the length, 

 height, or breadth. If the proportion between the representa- 



* Eesearches into the Physical History of Mankind, by Dr Pricliard ; vol. 

 iii. part i. pp. xvii to xxii.. As a copy of Dr Eschricht's memoir has just 

 reached us from the author, we may again recur to this interesting subject. 

 — Edit. 



t The paper of which this is an abstract was read before the Society of 

 Arts for Scotland, 22d March 1841, 



