The bill as it passed the House discriminated in favor of nations with which the United States had commercial treaties. That is to say, it favored France and Holland as against Great Britain, which had the bulk of America's foreign trade. Though Madison insisted on this provision and was supported by a large majority of the House, the Senate would not agree to it. During the early sessions of Congress the Senate met behind closed doors, a practice which it did not abandon until five years later. From the accounts of the discussion preserved in Maclay's diary it appears that there was much wrangling. Maclay relates that on one occasion when Pennsylvania's demands were sharply attacked, his colleague, Robert Morris, was so incensed that Maclay "could see his nostrils widen and his nose flatten like the head of a viper." Pierce Butler of South Carolina "flamed away and threatened a dissolution of the Union, with regard to his State, as sure as God was in the firmament." Thus began a line of argument that was frequently pursued thereafter until it was ended by wager of battle. On several occasions the division was so close that Vice-President Adams gave the casting vote. Although there was much railing in the Senate against imposts as a burden to the agricultural sections, yet some who opposed duties in the abstract thought of particulars that ought not to be neglected if the principle of protection were admitted. Duties on hemp and cotton therefore found their way into the bill through amendments voted by the Senate. Adjustment of the differences between the two houses was hindered by the resentment of the House at the removal of the treaty discrimination feature, but the Senate with characteristic address evaded the issue by promising to deal with it as a separate measure and ended by thwarting the House on that point.