48 Of Aliens coming into the Country. [Ch.IV. Sec.V^ It seems to have been the opinion of Lord Kenyon, that an exemption from impress cannot be founded on the common law, but only on a legislative provision (a). We have, how- ever, in the case of ferrymen, an instance of an exemption grounded merely on the common law {b) : and the express opi- nions of Lord Mansfield and Mr. J. Ashhurst, that as the right of pressing is grounded on the common law, an exemption from it may exist on the same foundation (c). Of course it is incumbent on the party insisting on the exemption to prove clearly the grounds on which he rests his claim to it {d). There is no doubt that the King may exempt or grant a protection to any particular class of seafaring men from im- pressment, because, in the Crown alone lies the power of is- suing press-warrants. In those warrants instructions are given to the officers not to impress any person protected by the navy, victualling office, &c. Even the officers themselves grant pro- tections ; a fortiori therefore if the officers, and inferior boards can grant protections, the Crown by its prerogative is entitled to the same privilege. These protections are however re- vocable at pleasure, though granted for a certain specified time (e). As conductor of a war the King is also entitled to adopt measures to prevent the egress or ingress of his enemies out of or into his Majesty's dominions. Thus his Majesty may pro- mulgate blockades ; may during war or threatened hostilities, and on occasions of emergency lay an embargo on all ship- ping ; and thereby prevent any one from leaving the king- dom [f). His Majesty may on the other hand permit an enemy to come into the country without molestation, by granting to him letters of safe-conduct (g). These letters ought to be under the Great Seal, and inrolled in Chancery [h). But pass- ports under the King's sign manual or licences from his ambas- (a) 5 Term Rep. 277. and see 1 Privy Seal is revocable. Post, tit. East, 166. Pardons, 1 Chitty, Crim. Law, 770. (A) See Sav. 14. 5 Term R«p. 277. So of a license to trade. per Buller, J. (/) Skinner, 335. 3 Lev. 552. 4 (0 Cowp. 518. 521, 2. Mod. 176, 177, 179. 1 Bla. Com. 870, 1. (rf) Ibid. 519. 4 Bac. Ab. 595. title Merchant and (<f) 16 East, 165. Cowp. 521. See Merchandize, see further, post. ch. 10, «t. 50 Geo. 3. c. 108. ante, ch. 3. (g) See Ld. Raym. 382. 1 Salk. 46. as to exemptions in general. Lane, 46. Lutw. 34, 5. Dyer, 176, 177. So a pardon not {h) 15 Hen. 6, c. 3. 18 Ibid. c. 8. under Great Seal but merely under 20 Ibid. c. 1. sadors
