10 In the particular case of the Western Australian legislation, the clear indication in the long title of the Secret Commissions Act, 1905 that its purpose was "the prohibition of secret commissions and rebates" adds considerable force to the conclusion that "corruptly" refers to the "corruption of agents" (words that appear in the chapter heading in the Code) by the surreptitious receipt, et cetera, of an inducement or reward. If s 529 and s 530 are "ambiguous or obscure", the section headings may be relied on also: Interpretation Act 1984, s 19; and see Pearce and Geddes on Statutory Interpretation in Australia, 4th ed (1996) s 4.40. The most relevant definition of the adjective "corrupt", from which the adverb "corruptly" derives, in the Shorter Oxford English Dictionary (1988 reprint) is "[i]nfluenced by bribery or the like". The sections, however, are not concerned with the whole universe of corruption, but with that which is related to the performance of the duties of an agent (although agency is to be perceived, by s 546, in an amplified sense). In this context, corruption involves a betrayal of trust, or at least a debasement of the disinterestedness a principal is entitled to expect of an agent. Corruption, so understood, does not sit with openness, and certainly not with a true assent by the principal.