1 , 9 - dihydroxyoctahydrobenzoquinolines , 1 - hydroxyhexahydrobenzoquinoline - 9 - ones , and 1 - hydroxy - tetrahydrobenzoquinolines useful as cns agents , especially as analgesics and tranquilizers , as hypotensives , as agents for the treatment of glaucoma and as diuretics ; intermediates therefor and derivatives thereof having the formulae ## str1 ## wherein r is hydroxy , alkanoyloxy having from one to five carbon atoms and hydroxymethyl ; r 1 is hydrogen , benzyl , benzoyl , alkanoyl having from one to five carbon atoms or -- co -- p -- nr 2 r 3 wherein p is 0 or an integer from 1 to 4 ; each of r 2 and r 3 when taken individually is hydrogen or alkyl having from one to four carbon atoms ; r 2 and r 3 when taken together with the nitrogen to which they are attached form a 5 - or 6 - membered heterocyclic ring ; r 4 is hydrogen , alkyl having from 1 to 6 carbon atoms and -- z -- c 6 h 5 wherein z is an integer from 1 to 4 ; r 5 is hydrogen , methyl or ethyl ; r 6 is hydrogen , -- y -- carbalkoxy having from 1 to 4 carbon atoms in the alkoxy group wherein y is 0 or an integer from 1 to 4 ; carbobenzyloxy , formyl , alkanoyl having from two to five carbon atoms , alkyl having from one to six carbon atoms ; -- x -- c 6 h 5 wherein x is an integer from 1 to 4 ; and -- co x - 1 -- c 6 h 5 ; r o is oxo , methylene or alkylenedioxy having from two to four carbon atoms ; r &# 39 ; is r or r 0 ; z is alkylene having from one to nine carbon atoms ; -- m -- x -- n -- wherein each of and is alkylene having from one to nine carbon atoms , with the proviso that the summation of carbon atoms in plus is not greater than 9 ; each of m and n is 0 or 1 ; x is 0 , s , so or so 2 ; and w is hydrogen , methyl , ## str2 ## wherein w 1 is hydrogen , chloro or fluoro ; pyridyl , piperidyl , cycloalkyl having from 3 to 7 carbon atoms , or monosubstituted cycloalkyl wherein the substituent is ## str3 ## wherein w 2 is hydrogen , chloro or fluoro ; and pharmaceutically - acceptable acid addition salts of compounds of formulae i , ii and iv and the ketals of compounds of formulae ii , iii and iv wherein the ketal moiety has from two to four carbon atoms .