356 THE SOVEREIGNTY OF THE SEA 



But they will be remembered in the history of international 

 law for another reason. The first of them called forth from 

 Grotius the only reply he ever vouchsafed to the numerous 

 writers who attacked Mare Liberum. In the year in which 

 the work was published, he was in London as one of the 

 Dutch ambassadors, engaged in the somewhat ironical task 

 of defending a Dutch mare clausum in the East Indies, and 

 probably the book then fell into his hands. In his Defensio 

 (see p. 344) Grotius reaffirmed the position he took in Mare 

 Liberum, with the old arguments, and with some new ones to 

 meet the criticism of Welwood, and not without some of the 

 customary logic-chopping and wire-drawn reasoning. He held 

 that the Roman law as to the sea being common applied not 

 merely among the citizens of one state, but among mankind 

 in general, because communis was a different thing from 

 publicus. 1 While admitting the possibility of marking out 

 the sea by imaginary lines, he said this was not relevant 

 to the question of appropriation, since appropriation could 

 not take place without possession, and possession cannot be 

 established merely by the mind or intellect, but requires a 

 corporeal act; otherwise the astronomer might lay claim to 

 the heavens or the geometrician to the earth. Concerning 

 the rights of fishery, with which the Defensio largely deals, 

 he asserts that as the use of the sea is common to all, no 

 one can prohibit fishing in it or justly impose taxes on it. 

 With respect to the right of the Dutch to fish on the British 

 coasts, he cites the Burgundy treaties and uses the same 

 arguments as the Dutch ambassadors did in 1610 (p. 155). 

 They had the right by treaties, immemorial usage, prescription, 

 and the Law of Nations. It is noteworthy that in the Defensio, 

 Grotius, no doubt owing to the polemical spirit inciting 

 him above all to refute the arguments of Welwood concerning 

 the mare proxi r mu r m, as well as to demolish the claims of 

 King James, denies the existence of sovereignty or property 

 in any part of the sea, whereas it appears to be allowed 

 by implication in Mare Liberum, and is expressly admitted 

 in his later and larger work. Here he says, and more 



1 In Roman law a distinction was made between the sea and rivers in regard 

 to propriety. The sea is " communis omnium naturali jure, " but the rivers are 

 "publicce res, quarum proprietas est populi vel reipublicce." 



