Note A. The above prices are per barrel. The price for the proof of a barrel or tube which does not fall within any of the above classes shall be per proof shot fired per barrel or tube respectively such sum as the two companies shall from time to time deem reasonable having regard to the cost and labour and in any case not more than one shilling and sixpence or twice the cost of materials used in such proof shot (whichever is the greater).

Where no price is provided for provisional proof the price which may be demanded and taken for such provisional proof shall not exceed the price provided in respect of the definitive proof of a barrel or tube of similar gauage.