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REPORT OF THE No. 3 



Radio. 



Radio communication, which was first tested in the period 1924-1925, was 

 utilized during the past season for communication in the Hudson Inspectorate. 



Operating with a main base at Sioux Lookout and three outside stations at 

 Pine Ridge, Red Lake and Long Lake, the system handled over one thousand 

 messages for a total of over fifty-eight thousand words. This increase in 

 traffic is well illustrated by the records of the Sioux Lookout station, where 

 thirteen hundred words handled in July — the opening month — increased to 

 twenty-seven hundred in August, and again increased to thirty-seven hundred 

 in September. Should the above condition continue during the coming season, 

 it will be necessary to obtain authority either to inaugurate a charge system or 

 to limit the number of messages accepted on any one day. 



Horizon Map. 



No practical results have as yet been obtained in this line of work. Briefly 

 stated the problem is to provide a diagram or special map which can be used 

 to relate the ordinary topographic sheet used in Forestry Branch towers to the 

 landscape as seen by the tower observer. In the case of a tower which has been 

 long established, in thoroughly mapped country, operating with a thoroughly 

 competent and experienced tower man, the importance of a horizon map is 

 negligible. Unfortunately, for a variety of reasons, these conditions do not 

 apply to many O.F.B, towers already established. It should be noted further 

 that the development of the horizon map contains the possibility of ma'terially 

 reducing the number of towers required in any territory, with a consequent 

 saving in capital and overhead expenditure. 



During the past season two photographic methods of preparing horizon 

 maps were tested in co-operation with the Tweed District office. In the first 

 of these, photographs were taken with a special photo-theodolite loaned by the 

 University of Toronto. This instrument, which is specially designed for survey 

 work, produced very sharp negatives. It was found, however, that in enlarge- 

 ment much of the desired detail was lost. A projection was, therefore, thrown 

 on drawing paper and the detail required, which could be quite readily picked 

 out, traced in by hand. The product of this experiment while partially suc- 

 cessful was considered too costly. 



Later in the season a special camera was constructed by the district staff 

 and a set of experimental photographs obtained. While still not entirely satis- 

 factory, these would appear to contain the essential information required. 



Photographic Survey. 



During the past season over two thousand aerial survey photographs were 

 taken, a total which more then exceeds all previous Branch work of this kind. 



Twoinajor improvements in the office end of the Branch's methods should 

 also be recorded; first, in the development of aerial film and, second, in the 

 final construction in workable form of a perspective pantograph. 



By the use of our own developing outfit, negatives and prints have improved 

 very markedly. It has also been possible with this equipment to maintain 

 much better co-operation with the photographers in the field than when devel- 

 oping and finishing were done by an outside organization. 



The photographic plotting apparatus mentioned above, which has been 

 constructed to a design evolved by members of the Branch, has proved successful. 

 By its use plotting can be carried on twice as rapidly and with a considerable 

 increase in accuracy. The apparatus is capable of still further development. 



