The appellant laid great emphasis on the use of the word 'claim ' in the opening part of cl. 18 and contended that the Standard Form of Contract which was in use prior to the adoption of the present Standard Form of Contract, cl. 14, and which corresponded to the present cl. 18, opened with the words " whenever under this contract any sum of money is recoverable from and payable by the contractor", but this formula was deliberately and advisedly altered when the present Standard Form was introduced and instead, the words "whenever any claim for the payment of sum of money arises. " were substituted and this change in phraseology indicated that in order to attract the applicability of the present cl.18 it was not necessary that there should be a sum due and payable by the contractor to the purchaser but it was enough if there was a mere claim on the part of the purchaser for payment of a sum of money by the contractor, irrespective of whether such sum of money was presently due and payable or not.