102 



ROYAL SOCIETY OF CANADA 

 TABLE XI. 



Observation Station 



Number of Location 



Station. 



Remarks. 



Value of " q ", the no. of ion» 

 generated per ce. per second. 



1. The ice on Toronto Bay, 



100 metres from the 

 Yacht Club Wharf. 



2. The ice nearCanoe Club 



Wharf, Toronto Bay. 



3. The ice on Grenadier 



Pond, an inlet of Lake 

 Ontario, Station " a." 



4. The ice on Grenadier 



Pond, Station " b." 



At the shore of Grena- 

 dier Pond, Station "c." 



On a sand hill over- 

 looking Grenadier 

 Pond. 



7. University Lawn. 



8. University Tower. 



9. In the open on the 



ground in the rear of 

 the new Physical La- 

 boratory. 



10. A room in the basement 

 of tlie new Physical 

 Laboratory. 



Water, 10 metres 



deep 



Ice, 30 cms. thick. 



Water, 5 . 6 metres 



deep 



Ice, 30 cms. thick. 



Water, 2 . 5 metres 



deep 



Ice, 30 cms. thick. 



Water, 3 . 5 metres 



deep 



Ice, 30 cms. thick. 



Height of hill about 

 50 metres distance 

 from shore, 100 me- 

 tres 



Clay, soil, sodded, 

 frozen and covered 

 with ice and snow^, 

 20 cms. deep 



26 metres high 



Frozen clay, recently 

 overturned, covered 

 with 10 cms. of ice 

 and snow 



As the building is new, 

 it was supposed to 

 be free from any 

 radioactive conta- 

 mination 



Lead. 



9.0 



8.6 



9.2 



9.0 



9.1 



9.3 



11.2 

 11.4 



13. 2 



15.3 



Zinc. Aluminum 



6.0 



6.55 



11.1 



13.4 



10.4 



12.5 fi 



From the observations with the lead cylinder it will be seen that 

 the ionization obtained over water of different depths was practically 

 constant, the value for " q " being, as before, but slightly less than that 

 obtained above a sandy soil. It is important to note also that the 

 ionization on top of the university tower was the sar^e as that found 

 below on the campus, indicating that the atmosphere could not be the 

 source of the penetrating radiation which gave the variation noted in 

 the values of "q " for the air confined in a doised metallic receiver. 



