24 



KNOWLEDGE 



[January 1, 1896. 



Black, 



Here, then, are the positions, which anyone who works 

 methodically can discover for himself in an hour or two. 



A.— a1, 15, c8, d6, e3, f7, g2, h4. (a) 



b6, c8, d3, e7, f4, g2, h5. (/3) 



h7, c4, d6, e8, f2, g5, h3. (/3) 



c5, d8, e2, f4, g6, h3. (a) 



B.— a2, W, c6, d8, 83, fl, g7, h5. (A) 



h5, c7, dl, e3, f8, gG, h4. (^) 



d4, el, f8, g6. h3. (■>)) 



hC, cl, d7, e4, f8, g3, h.5. (J) 



c8, d3, el, f4, g7, h.5. (k) 



/'7, c3,d6, e8, f5, gl, h4. (y) 



c5, d8, el, f4, gG, hS. (fl) 



ftc9,cG, dl, eS, f5, g7, h4. (y) 



C— a3, hi, c7, d.5, e8, f2, g4, h6. (8) 



i.5, c2, d8, el, f7, g4, h6. (wj) 



[Diagram of the symmetrical position (coj).] 



eG, f4, g7, hi. (/3) 



c7, dl, e4, f2, g8, h6. {S) 



c8, d4, el,f7, g2, h6. (i) 



h6, c2, d.5, e8, fl, g7, h4. (e) 



d7, el, f4, g8, h5. (?) 



e5, fl, gS, h4. (^) 



c4, dl, eH, f5, q7, h2. (6) 



d2, e8, /5, r//", hi. (a) 



c8, dl, e4, f7, g5, h2. {yj) 



e5, f7, g2, h4. (.) 



d2, e4, fl, g7, h5. (i) 



hi, c2, d8, e5, fl, g4, hG. (i) 



eG, f4, gl, h5. (k) 



/'8, CO, d7, el, fO, g2, h5. (A) 



D. a4, hi, c5, d8, e2, f7, g3, hf,. (^ 



c5, dS, e6, f3, g7, h2. {y) 



b3,c5,d8,e6,n,g3,h7. (k) 



c7, d3, eG, f8, </h ''5. (9) 



.'/5, W. (a) 



d5. el, f8, g6, h3. (e) 



c8, d5, e7, fl, g3, hG. |«i 



dG, el,f3, g5, h7. (>.) 



/j6, cl, d5, e2, f8, g3, h7. (^'i 



CH, d2, 87, fl, g3, h5. (a;,,) 





[Diagram of the Symmetrical Position (w^).] 



d3, el, f7, g5, h2. 



hi, cl, d8, e5, f2, gG, h3. 



c3, d8, e2, f5, gl, hG. 



c5. d2, eG, fl, g3, h8. 



d3, el, fG, g8, h2. 



/-8, cl, d3, eG, f2, g7, h5. 



d5, 87, f2, gG, h3. 



c5, dl,e3, f7, g2, hG. 



These are evidently half the possible positions, which 

 must be ninety-two in number. Any position beginning 

 with a5 must be practically the same as one beginning 

 with a4. So a6 is akin to a3, a7 to a2, and a8 to a1. 



Contents op No. 122. 



(0 



(^) 

 {&} 



(y) 

 («) 



(«) 



280 



270 



PAGE 



New Stars. By Dr.A.Brester.Jun. 27S 

 The Exterior Nebulosities of the 



Pleiades. By Miss A.M. Gierke. 



tlUuslmled) 



On the Exterior Nebulosities of 



the Pleiades. By Prof. E. E. 



Barnard 282 



Spectrum Analysis. — III. By J. J. 



Stewart, B.A.Cantab., B.Sc. 



Lend, (niuslrated) 282 



Mistletoe and Mistle Thrush. By 



Graham W. Mni-doch 2»t 



Some Recent Patents. (TUus- 



trated) 



The Face of the Sky for Decem- 

 ber. By Herbert Sadlei-.F.E.A.S. 

 Chess Column. By C. D. Locock, 



B.A.Oxon 287 



Two Plates. — 1, The Golden Eaple's Eyrie, with younj; and prey ; 2, Photo- 

 graph of the Nebulo&ities surrounding the Pleiades, 



PAGE 



The Krakatoa Eruption. By Rev. 



E Rattenbnry Hodges. (Illus- 



iratedj 265 



The Golden Eagle 269 



The Filtration of Water.— II. By 



Samuel Eideal, D.Sc.Lond., 



F.I.C., F.CS 



Whip-Scorpious and their Ways. 



By E. I. Pocock. {Illustrated) 'ITi. 



Notices of Books 274 



Ai'rial Warfare. By Thomas Moy 276 



Science Notes 276 



Letters : — Alfred J. Johnson ; Un 



Vieil Etudiaut (JUustroted) ; 



J. Willis, Ph.D. (IUus(ra(cd) ; 



T. (lili/sfrafed); William Noble ; 



Isaac Roberts 277 



285 

 286 



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