770 THE BELL SYSTEM TECHNICAL JOURNAL, MAY 1953 



ceming reflection processes at a metal surface and the nature of electron 

 ejection by the alpha-particle (He++) and the molecular hehum ion (He2+) 

 come out of this work. 



Heidenreich, R. D. 

 Methods in Electron Microscopy of Solids, Rev. Sci. Instr., 23, pp. 

 583-594, Nov., 1952 (Monograph 2047). 



Methods of replicating solid surfaces for electron microscopy are reviewed 

 and compared. Preparation of metal surfaces for electron microscopy is dis- 

 cussed, and the advantages of employing electron diffraction techniques 

 in evaluating prepared surfaces are pointed out. Examples of the appUcation 

 of replicas include steel, precipitation in alloys, such as Alnico 5, and studies 

 of slip in aluminum. Growth spirals on the surfaces of crystals of w-paraffins 

 are demonstrated. The use of thin metal sections and of emission electron 

 microscopy in studying metallic structures is discussed, and examples are 

 given. 



Hutchinson, A. R.^ 

 How to Conceal Telephone Wires, Keep Desks Neat, Standardiza- 

 tion, 23, p. 407, Dec, 1952. 



Jakes, W. C, Jr.^ 

 Theoretical Study of an Antenna-Reflector Problem, I.R.E., Proc, 

 41, pp. 272-274, Feb., 1953. 



This paper gives the results of a theoretical investigation of an antenna used 

 with a plane reflector. This finds application in microwave relay stations, 

 where the antenna is placed at ground level facing up and the reflector is 

 located some distance above it. The results given show that there are certain 

 values of X, separation distance, reflector and antenna size for which the 

 received power is greater than for the same antenna alone at the elevated 

 location. 



Kaplan, E. L.^ 

 Tensor Notation and the Sampling Cumulants of k-Statistics, Bio- 

 metrika, 39, pp. 319-323, Dec, 1952. 



Now and then in the Uterature one finds results relating to multivariate 

 distributions which are derived virtually independently of, or with con- 

 siderable effort from, the corresponding univariate relations, whereas they 

 are in fact only very mild generaUzations of the latter, as will be shown. 

 Only the famiUar concepts of moments, characteristic functions, cumulants, 

 and A^statistics and their sampling cumulants will be discussed here. It should 

 be emphasized that these concepts are identical with those ordinarily used in 

 multivariate situations; the only novelty lies in the concise manner of repre- 

 senting and handling them. 



' Bell Telephone Laboratories, Inc. 

 ' Western Electric Company, Inc. 



