19. _Alteration and suspension of by-laws._--It shall be lawful for the Conservators, in addition to all powers of making by-laws already possessed by them under the Acts mentioned in the First Schedule hereto, to make, and from time to time to suspend or alter in the same manner and with the same consent as in the same Acts is provided, all by-laws which they may deem necessary for the purposes mentioned in this Act, or in the Second Schedule hereto. 20. _Continuing offences._--Any act or default in contravention of any of the said by-laws or of the provisions of this Act, which after due notice is repeated or continued, shall be a continuing offence under this Act. PART IV.--PROCEDURE. 21. _Penalty for offence against the Act._--Any person convicted of an offence under this Act shall, where no other penalty is provided by this Act or any of the Acts mentioned in the First Schedule hereto, or by any by-law made thereunder respectively, be liable to a penalty not exceeding forty shillings. 22. _Penalty for continuing offence._--Any person convicted of an offence which is a continuing offence under this Act shall, where no greater penalty has been provided for such offence by any of the Acts mentioned in the First Schedule hereto, be liable to a penalty not exceeding five pounds. 23. _Jurisdiction of certain justices._--For the purposes of this Act, and of every by-law to be made by the Conservators thereunder, the jurisdiction of all justices of the peace for the counties of Surrey, Berkshire, Wiltshire, Gloucester, Oxford, Buckingham, and Middlesex, and of the magistrates for the city of Oxford, and of every other borough, the police jurisdiction of which extends to any place upon the River Thames within the limits aforesaid, and the jurisdiction, powers, and authority of the Proctors of the University of Oxford and the marshals and officers acting under them, and the power and authority of the Metropolitan Police, and of all police officers and constables acting for any of the said counties or boroughs, shall extend over the whole of the River Thames, and the towpaths, banks, and precincts thereof, within the limits aforesaid. 24. _As to place where offence committed._--For the purposes of any proceedings in respect of any offence under this Act, or under any of the Acts mentioned in the First Schedule hereto, every such offence shall be deemed to have been committed, and every cause of complaint in respect thereof shall be deemed to have arisen either in the place in which the same actually was committed or arose, or in any place in which the offender or person complained against may be.