Note the parallel construction of the predicate adjectives "small," "dark," "ugly," and "incommodious," and then, parallel to that, their repetition as objects of prepositions.

     Tellson's Bank {by Temple Bar} was an old-fashioned place (PN),

even {in the year} one thousand seven hundred and eighty. ^[#1]  | It was

very small (PA), very dark (PA), very ugly (PA), very incommodious

(PA). |  It was an old-fashioned place (PN), moreover, {in the moral attribute} 

[Adj. to "attribute" that the partners {in the House} were proud (PA) 

{of its smallness}, proud (PA) {of its darkness}, proud (PA) {of its ugliness},

proud (PA) {of its incommodiousness}]. |  They were even boastful (PA)

{of its eminence} {in those particulars}, and were fired ^(P) {by an express

conviction} [Adj. to "conviction" that, [Adv. (condition) to "would be" if it 

were ^[#2] less objectionable (PA)], it would be less respectable 

(PA)]. | This was no passive belief (PN), but an active weapon (PN) 

[Adj. to "weapon" which ^[#3] they flashed {at more convenient places}

{of business}. |