The Tyne keelmen, while ostensibly consenting to buy immunity on this basis, seldom levied the quota upon themselves. By offering bounties they drew the price of their freedom to work in the keels from outside sources. Lord Thurlow confessed that he did not know what "working in the keels" meant. [Footnote: _Admiralty Records_ 7. 299--Law Officers' Opinions, 1752-77, No. 70.] There were' few in the fleet who could have enlightened him of their own experience. The keelmen kept their ranks as far as possible intact. In this they were materially aided by the Mayor and Corporation of Newcastle, who held a "Grand Protection" of the Admiralty, and in return for this exceptional mark of their Lordships' favour did all they could to further the pressing of persons less essential to the trade of the town and river than were their own keelmen. On the rivers Severn and Wye there was plying in 1806 a flotilla of ninety-eight trows, ranging in capacity from sixty to one hundred and thirty tons, and employing five hundred and eighty-eight men, of whom practically all enjoyed exemption from the press. It being a time of exceptional stress for men, the Admiralty considered this proportion excessive, and Capt. Barker, at that time regulating the press at Bristol, was ordered to negotiate terms. He proposed a contribution of trowmen on the basis of one in every ten, coupling the suggestion with a thinly veiled threat that if it were not complied with he would set his gangs to work and take all he could get. The Association of Severn Traders, finding themselves thus placed between the devil and the deep sea, agreed to the proposal with a reluctance they in vain endeavoured to hide under ardent protestations of loyalty. [Footnote: _Admiralty Records_ 1. 1537--Capt. Barker, 24 April and 9 May 1806, and enclosure.] In the three hundred "flats" engaged in carrying salt, coals and other commodities between Nantwich and Liverpool there were employed, in 1795, some nine hundred men who had up to that time largely escaped the attentions of the gang. In that year, however, an arrangement was entered into, under duress of the usual threat, to the effect that they should contribute one man in six, or at the least one man in nine, in return for exemption to be granted to the remainder. [Footnote: _Admiralty Records_ 1. 578--Admiral Pringle, Report on Rendezvous, 2 April 1795.]