1'n; 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



0.0005 0.0010 0.0015 



TIME IN SECONDS. 



Figure 7. (Tables XXVI, XXXIV-XXXVI, XXXVIII.) 



0.0008 0.0010 0.0015 



TIKE OF CHARGIHQ. 



Figure 8. (Tables XLII and XLIII.) 



