The drug has been shown to be effective in combating most Gram-negative micro-organisms, including Esch. coli, Klebsiella, and B. proteus, in vitro and in vivo (Barlow, 1963; Buchbinder, Webb, and McCabe, 1962; Lesher et al., 1962), though Pseudomnonas appears to be more resistant (Barlow, 1963; Buchbinder et al., 1962; Harper and Howse, 1964). Gram-positive bacteria such as staphylococci, ente...