EDITORIALLY SPEAKING Tn thc Editor: As a college teacher, I am somet,imes a hit puzzled ahnut what, to teach. For example, "Thr di.~mrt~r of xn electron, approximately 22 X 10-fl inch, is nlmlt thrcr times t,he diamet,er of n prot,on!' TM11-fi!?O, 1L S. AN!,.!/, p. 16. Arconling to th? familiar Huhhnw-Meygers Periodic Chad elrrtrous and protons hnvt idrntical diamet,ers, 2.8 X I O W 3 rm. Ph~i"irn1C h m i s t n ~ I,,? A. .I. Kntgers, p. 25, lists "Radios of prnton (cnlr.), 1 0 - I ' rm.; radius of rlert,ron, (calc.), 10P3cm. S. (;lnsst,onr's Sow-e~book,p. 40,says: "J. J. Thom~onin 1881 had drrivcd n n rqmtion, from theoretical principles, relat,ing thr rlwfromngnrtic mass 1n of x spherical chnr~edpart,ieleof ratlirw r to its charge r ~xprefis~d in emu . . . thus, r = 2 8 / h . . , in so far R R an t4r.rtron m n 1w rrrsrded as having x definite redins . . ., it is pml':~l,lymfc to s ; q that it is ahout 2 X 10WJcm."
Since the proton has ahout 1837 times t,he mass of the electron, Thomson's formula predict,s t,hat, the protcm radius is only 1,/1837 that of the electron, in rough agreement TX-ith Rut,gerls figures. In the interest of cooservation of studeut time it, mould be nire to establish whet,her this quest:ion falls in the class of "\Vhat color would an elephant's egg be if an elephant laid eggs?" I s an experiment,al answer possible? From the Editor: (Aftrr ronsnltntion with Prof. K. J. Stephenson of the Collrgr of Rrwrst,I ~vouldn'trare ior (lare) to comment unon. I just don't knonm what "larger" means. I agree with you 100 per rent. I h,opc wr can all help students to think "in tmns (11thr mid-twuntieth crnlury scienflfic approachrs." Volume 38, Number
3, March 196 1
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