United States. Surgeon-General's Office, American Roentgen Ray Society · New York : Middleditch · leaf 43
econds are re-quired, at 20 inches 2 x ( —) =. 2 x —>: at 25 inches\15/ 9 OK /^0\2 2 x -^ , at 30 inches 2 x ( ~ J =2x4 = 8 Sec, etc. KV. f : - f 1 ■■ I :£ 1 St :::: Jii( 60 i — —— rrH« ■:■:■:. •i ::i: SO40 p_ J el:: ::::|:::;hin * 30 — J ?^ ip -r^- £ li\\ / :.;■ 20 ;::: / lV:\ / -:*: iiii- ,-:… … Fig. 12. Relation between kilo-volts and spark gap between blunt points.A four inch gap should read 50 K.V. etc. 36 X-RAY PHYSICS 37 Amount of Radiation. The measurement of Roentgen radiation has proved arather difficult matter and need not be fully discussedhere. For our purpose the photographic…
