ABSTRACTS OF TECHNICAL ARTICLES 513 



satisfaetoril}' cover the space between tlie ])ictures ])r<)vi(Ie(l by any one 

 camera. Tliis ])apor liives a method for estimating the prolwbility that the 

 longest interval witliout a pictuie will not exceed a selected value. 



WiLLL\MS, H. J./ \{. C 8iii:r\vood/ M. Goertz^ and F. J. Sciinettler.' 



Stressed Ferrites Having Rectangular Hysteresis Loops, A.I.E.E. 

 Trans., Commun. & Electronics, 9, pp. 531-537, Nov., 1953. 



A study has been made of the effect of stress on the magnetic ])roperties of 

 ferrites. Rectangular hysteresis loops were obtained by encasing toroidal 

 specimens in i)lastics which shrink during polymerization. Ferrites having 

 this type of hystersis loop are useful in magnetic switching and magnetic 

 memory devices. 



Williams, N. T., see R. Kompfner. 



Wright, S. B.^ 



Higher Frequencies, Aero Digest, 67, pp. 66, 70, 72, Nov., 1953. 

 Spectrum ero\vding plus new techniques has moved USAF ground-air 

 communications into the ultra-high-frequency bands. 



Correction 



On page 878 of the July, 1953, issue of the Journal, an error was 

 made in quoting the number of P. H. Richardson's patent in Reference 

 5. It should have been 2,348,572. 



