Canadian Forestry Journal, April, ig20. 



187 



permit of rapidly designating an ex- 

 ceedingly small area. 



Various methods of rapid refer nee 

 by 'map squaring' were used by all 

 the belligerent countries during the 

 Avar, but the areas dealt with were 

 seldom as extensive as those Avhich 

 confront us in Canada. An index 

 system covering the whole universe 

 was drawn up by an Internationa^. 

 Conference some years ago, and al- 

 though this will probably be used by 

 all countries for long distance aerial 

 transportation work, it is entirely un- 

 suitable for "intensive" aviation such 

 as is being inaugurated in the Pro- 

 vince of Quebec, chiefly by the pulp 

 and paper industry. 



How the System Works Out. 



The system illustrated concerns 

 mainly the Province of Quebec. The 

 area contained between the parallels 

 45°N and 52°N, and the meridians 

 6o°\\ and 80° W, has been taken as 

 that embodying all th j territory in 

 the province of interest to aviation. 

 Beginning at the south-west corner 

 of this territory, areas contained be- 

 tween deerees of latitude and lonei- 



tude are numbered from west to east, 

 and in consecutive rows northwards, 

 notation being from r to 140 for the 

 complete territory. The degrees of 

 longitude are then divided into two 

 equal parts, measuring along the 

 parallels ; and the degrees of latitude 

 are divided into three equal parts 

 measuring along the meridians. This 

 divides each of the spaces enclosed 

 l)y a degree of latitude and longitude 

 into six parts which are designated 

 by the letters A, B, C, D, E, and F, 

 in each degree. Each of these letter- 

 ed divisions is sub-divided into twen- 

 ty-five parts, which are measured 

 from I to 25. By referring to the il- 

 lustration it will be seen that the 

 position of Ottawa would be given 

 as 5 C 19. This refers to an area 

 about five miles square, which is ac- 

 curate enough for most purposes. 



Finer Sub-divisions. 



An even finer division, not shown 

 in the illustration, has frequently to 

 be used on large scale maps where 

 accuracy of location is necessary, as 



How the province of Quebec would look to the Hying man, equipped with the reference map. 



