128 



REPORT OF THE 



No. 7 



of either is less than one hundred pounds, the battery set being somewhat 

 lighter. In point of initial cost, the power driven set is at a disadvantage, while 

 in point of upkeep, the battery set suffers. On the whole, it would appear that 

 the power-driven outfit will be more generally desirable. 



The aerial set which was designed and tested during the past season differs 

 from all other Department equipment in the fact that it provides one way 

 communication only. Considerable difficulty was encountered in obtaining 

 material for this apparatus owing to its special nature and also to the general 

 rapid development of the radio industry. During the present season, this delay 

 was particularly unfortunate since it led to the arrival of this material coinciding 

 with a period of very high fire hazard and consequent flying activity during 

 which it was impossible to lay up a machine loj;ig enough to permit of an installa- 

 tion being made. The equipment did not therefore receive a working test until 

 near the close of the season. The test was successful and it is now considered 

 that a much less powerful apparatus would supply all requirements. Present 

 indications are that it would be desirable to lighten the apparatus and supply 

 two-way communication. 



Miscellaneous Investigations. 



(a) A method of providing data for the construction of contour maps from 

 aerial survey photos was investigated in a portion of the Georgian Bay District 

 during the month of September. Results have not as yet been completed, but 

 the field work proved both rapid and simple. The method which comprises 

 features of outstanding worth is based on the use of surveying aneroids. Position 

 is fixed on photographic prints taken into the field, thus eliminating the necessity 

 of chainage. 



(b) Little progress was made in the matter of tower horizon maps. The 

 Kodak Company have, however, undertaken to conduct a series of investigations 

 as to the most suitable apparatus. 



COMMERCIAL TRAFFIC 



Commercial Stations, Hudson District 



Nov. 1st, 1928, TO Oct. 31st, 1929 



Total Commercial Trafific 315,272 words 



m 



