>; 
detected. À possible application of this method to a study 
of the Gulf Stream is being considered. Rocket photography 
of cloud masses may give wind or air mass velocities. 
In conclusion the writer wishes to thank all 
those who have contributed to this work. They include 
officers and men of the R.C.A.F. and the RB.C.N., offioials 
of the Topographic Survey, the Defence Research Board, and 
the Dominion Public Works Department. Special thanks are 
due to the Nova Scotia Research Foundation, which 
Sponsored and encouraged this research. 
Halifax, N, Sg. 
March 11, 1960