Shannon Navigation Act, 1839

Commissioners shall cause Surveys and Maps of the Mills and all Weirs and Dams thereon to be made.

XL. And be it enacted, That the said Commissioners, at such Time and Times as to them shall seem expedient, and from Time to Time, shall cause Surveys to be made of the said River Shannon, or of any of the Rivers aforesaid, or of any Parts thereof respectively, and shall, if it seem expedient to them so to do, cause Maps or Plans to be made of the said River, or of any of the Rivers aforesaid, or of such Parts thereof as to them shall seem expedient, and shall in such Maps or Plans, or in the Maps or Plans heretofore made of such, accurately describe the several Weirs, Dams, Water-courses, and other Matters and Things which shall then be or stand or be placed or erected in the said River Shannon, or any of the Rivers aforesaid, or such Parts thereof as aforesaid; and the said Commissioners shall cause Copies of such Maps or Plans, or of the Maps or Plans heretofore made, or of such Plans thereof, as to them shall seem expedient, to be made and deposited in such and so many convenient Places in the Vicinity of such Rivers as they shall think proper, there to remain open to public Inspection at all reasonable Times for Three successive Weeks, and shall cause Notices of the Place or Places where the same may be deposited to be posted in the usual Places for posting Grand Jury Notices in each adjacent Barony or Half Barony, and a like Notice to be inserted once in each Week for Three successive Weeks in the Dublin Gazette; and the said Commissioners shall have Power during such Three Weeks to alter and amend such Maps, Plans, and Copies, according to any Evidence which shall be produced before them, or otherwise as to them shall seem expedient; and from and after the Expiration of such Three Weeks any such Map, Plan, or Copy as aforesaid, signed by the said Commissioners, shall be Evidence in any Court whatsoever that the Weirs, Dams, Watercourses, and other Matters or Things therein described existed, at the Time of the making such Maps, Plans, or Copies, in the respective Rivers therein named, and that the same were respectively of the Height, Extent, and Dimensions therein respectively described, and shall also be Evidence that no other Weirs, Dams, Watercourses, or other Matters or Things existed in any of such Rivers, or of such Parts thereof as aforesaid, save and except those contained or described in such Maps, Plans, or Copies thereof.