GEOMETRICAL AND ENGINEERING DRAWING. 



BY PROFESSOR T. F. PIGOT. 



IN the two lectures which I am about to deliver, I shall 

 confine myself as much as possible to an explanation of the 

 apparatus contained in this collection. In the teaching 

 of geometrical drawing, large recourse should be had to 

 models, and there is a fine collection in this exhibition, 

 which will be, in part, the subject of the present lecture. 

 The knowledge required by civil engineers for drawing 

 diagrams and designs of various kinds is of great extent, 

 embracing the many distinct branches into which civil 

 engineering is divided. Of these I may enumerate canals, 

 rivers, roads, railways, bridge construction (including 

 strength of materials), hydraulic engineering, harbours, 

 lighthouses, and finally, surveying, which is required for 

 all these purposes. This last, I understand, will be dealt 

 with in another lecture, so that I have no further reference 

 to make to it. 



It so happens that this exhibition, large as it is, is 

 singularly deficient in good models connected with the 

 subjects I have enumerated, except in the one case of 

 lighthouses ; and I have, therefore, selected the subject of 

 lighthouse illumination for my second lecture. It is true 

 that there are, scattered up and down through this 

 enormous collection, very many objects bearing on engi- 

 neering, such, for instance, as Mr. Clark's hydraulic canal 

 lift, which I believe is here ; a fine collection of rain-gauges, 

 wind-gauges, and current meters, besides a vast number of 

 drawings and models of steam-engines, and other machinery. 



