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Event table notes
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| Event data |  | 
   | Place: Philadelphia |  
   | Start date: 20 Mar. 1861 |  
   | End date:   Mar. 1861 |  |  |  
   | Notes: |  
   | The result is sometimes given as +6-3=2 for Leonard, but Hilbert makes clear that the 11th game was not really a draw, being unfinished, and the result of games played out was +6-3=1 for Leonard. The last day of play was 1 Apr. 1861 but if we don't count the 11th game, the last completed game was finished sometime in the last few days of March. The Era of 5 May 1861 (p.14) gives the starting date as 19 Mar. 1861. Hilbert gives 20 Mar. 1861. |  |  |  |  
   | References |  | 
| Books |  
   | Hilbert, Tragic Life of Leonard, page 94, 114 |  
   | Reichhelm and Shipley, Chess in Philadelphia, page 9 |  
   | Winter, Kings, Commoners and Knaves, page 139 |  | Periodicals |  
   | [Era], vol. 23, no. 1180, 5 May 1861, page 14 |  
   | [Era], vol. 23, no. 1186, 16 June 1861, page 5 |  
   | [GWT], 15 Feb. 1867 |  
   | [NYC], 30 Mar. 1861 |  
   | [NYC], 6 Apr. 1861 |  
   | [NYC], 13 Apr. 1861 |  
   | [NYC], 18 May 1861 |  | Web |  
   | Spinrad, Jeremy P.  [Collected results, 1836-1863] |  
   | Winter, Edward.  [James A. Leonard] |  |  |