The preparation of articles of impeachment against the Earl of Danby, Lord High Treasurer in the reign of Charles the Second, December 21, 1678, presented the same rule in another aspect. It was no longer a bill, but an inquiry or investigation, when the Speaker said:-- “No man, by the ancient rules of the House, is to be of a committee of a _thing_ he is against.”[33] Here the language is somewhat broadened, though in entire keeping with the other cases. A man cannot be on a committee “of a _thing_ he is against.” In other words, if he is against the inquiry for which a committee is created, he cannot be on it. And here again good faith requires that the rule should be observed not merely in form, but in substance. These cases were analyzed and adopted by Mr. Jefferson in his authoritative “Manual”; so that they have become American Parliamentary Law, as obligatory here as in England. Speaking always by their essential reason, but with the weight of precedent also, they are not less binding than if promulgated with an enacting clause. Mr. Jefferson furnishes other and most important words of his own:-- “And when any member who is against the bill hears himself named of its committee, _he ought to ask to be excused_.”[34] This is the language of our Manual, declaring the duty of a member who hears himself named of a committee on a bill he is against. Of course the general rule is applicable to any other matter referred to a committee. The words are, “he _ought_ to ask to be excused.” Of course his continuance on the committee, or any attempt to exercise its duties, is a violation of Parliamentary Law, unless you are ready to discard this positive injunction. Mr. Jefferson then adds, by way of illustration:-- “Thus, March 7, 1606, Mr. Hadley was, on the question being put, excused from being of a committee, declaring himself to be against the matter itself.”[35] And our great authority declares that this is “a constant rule.”[36] Such is Parliamentary Law; and Mr. Jefferson has answered in advance the possible objection, that this is English and not American. After saying, in his preface to the “Manual,” that the Senate has given to these rules “the sanction of their approbation,” he announces “the law of proceedings in the Senate as composed of the precepts of the Constitution, the regulations of the Senate, and, where these are silent, of _the rules of Parliament_.” Such, according to him, is the law of our proceedings. The “Manual” which he presents he hopes others may fill up, “_till a code of rules_ shall be formed for the use of the Senate, the effects of which may be accuracy in business, economy of time, order, uniformity, and impartiality.” The last word is “_impartiality_,” which, doubtless, is a main object to be secured. Any one disposed to neglect these rules will find a warning from Mr. Jefferson. In his opening chapter he quotes these words from the famous Speaker Onslow:--