...On the 3rd March 1870, the defendant being unable to act as referee under the said agreement, Mr. Coulcher was appointed referee in his stead by a memorandum of which the following is copy:

    "It is hereby agreed by and between the undermentioned parties that Mr. Martin Coulcher, of Downham, shall undertake the office of referee now accepted by Mr. J. H. Walsh, with full powers to name an umpire, as agreed on, and it is also agreed that Mr. Walsh shall pay to the order of the two referees or of the umpire agreed on by them, the sum of 1000l. now standing in his name at Coutts' Bank in London either to Mr. Wallace or Mr. Hampden as the case may be.

Alfred R. Wallace, John Hampden."

    It was agreed between the parties concerned that certain experiments and tests agreed on should be made and used on the Bedford Level Canal; and during the 3rd, 4th, and 5th March 1870, in the presence of the plaintiff, Mr. Wallace, Mr. Carpenter, and Mr. Coulcher, such experiments and tests were made and used. As the result of the said experiments and tests Mr. Coulcher came to the conclusion that Mr. Wallace had proved, and Mr. Carpenter came to the conclusion that Mr. Wallace had not proved, that the surface of the said canal was convex. The defendant was present when some of the experiments and tests were made and used.

    A few days after the said experiments an interview took place between Mr. Carpenter and Mr. Coulcher, when the latter insisted on an umpire being appointed, to which Mr. Carpenter would not accede; and on the 7th March 1870 the following letter was written by Wallace to the plaintiff, and received by him.

"9, St. Mark's Crescent,
Regents Park, N.W.,
7th March 1870.

    Dear Sir,—As Mr. Coulcher maintains that I have proved my case while Mr. Carpenter says I have not, and as the latter gentleman has refused to appoint an umpire, and has left Downham without doing so, I am informed that the duty of naming the umpire now devolves on you and me.

    I, therefore, beg you either to name two civil engineers of whom I will choose one, or allow me to name two for you to choose from, or what I think better still leave it to Mr. Walsh to name an engineer of reputation. If you adopt the latter plan, please write to him authorising him to do so and I will do the same.

    When the umpire is appointed, both the referees can send in their reports and sketches of the experiments, and the umpire will either decide on them if he thinks the thing plain, or will call on me to repeat the experiments before him, which, of course, I shall be ready to do if required. Waiting your reply. I remain, dear Sir, Yours very faithfully, Alfred R. Wallace.

J. Hampden, Esq." ...