In 1844, Mr. Wallingford entered the employ of the Cocheco Manufacturing Company, Dover, N. H., as master machine-builder, and remained in that capacity until 1849. During that period, Mr. Wallingford and a partner, by contract, constructed new machinery, cards, looms, dressing-frames, and nearly everything necessary for the re-equipment of the mills. The then new and large mill at Salmon Falls was also supplied with the new machinery necessary, in the same manner. In 1849 he became superintendent of the company's mills, under the then agent, Captain Moses Paul, and upon the death of that gentleman, was, on the first day of August, 1860, appointed agent of the company. He has continued to fill that office to the present time. Taking into account the great social and public influence, as well as the recognized ability with which his predecessor had for many years administered the affairs of the Cocheco company, the magnitude of its operations, the force and grasp of mind necessary to carry on its affairs successfully, it was evident to all familiar with the situation upon the death of Captain Paul, that no ordinary man could occupy the place with credit to himself, or to the respect of the public, or the satisfaction of the corporation. Fully conscious of the responsibility assumed, and full of the determination which an ardent nature is capable of, not only to maintain the reputation of his company but to extend its operations and raise the standard of its manufactured goods, it is not overstating the fact to say that in the last twenty years few manufacturing companies have made greater strides in the extent of their works, in the quality of their goods, or their reputation in the great markets, than has the Cocheco under the management of Mr. Wallingford. Always strong financially, its wheels have never, during that time, been idle in any season of panic or monetary depression. Honorable, and ever generous to all its employes, its machinery has never stopped for a day at the demand of any organized strike. The pride, as well as the main business interest of Dover, Mr. Wallingford has always made his company popular with the people; its word proverbially is as good as its bond. The importance of the work is seen in the fact that the mills were, when Mr. Wallingford took charge, of a so-called capacity of fifty-seven thousand spindles; it is now one hundred and twenty thousand; and the reputation of the goods is world-wide. Twelve hundred operatives are on the books of his charge.