It was in connection with these efforts to aid the farmers that Prof. Henslow made the memorable discovery of the agricultural value of the so-called coprolites, or phosphatic nodules, found in the red crag at Felixstowe, in Suffolk. They were shown to contain 56 per cent. of phosphate of lime, and therefore to be capable of replacing bones in fertilization. He called attention to the similar concretions abundantly distributed in the upper greensand of Cambridgeshire, which were even richer in phosphate, and which have since yielded immense profits both to the proprietors of the pits and the farmers who used the product.
Prof. Henslow had paid much attention to entomology; and his knowledge of plants, and the parasitic insects which infest them and destroy the crops, enabled him to instruct the farmers upon this subject. He closely investigated the diseases of wheat, potatoes, and clover, and diffused the results of his inquiries in lectures, tracts, and newspaper correspondence.As he lived in an agricultural community, in which all were interested in farm products and processes, Prof. Henslow resorted to other means of quickening the general interest in these matters, and of enlisting the sympathy of laborers as well as farmers. For this purpose he instituted horticultural shows, at which there was a distribution of prizes for such products as wheat, fruit, flowers, vegetables, and honey, and sometimes for works of mechanical ingenuity calculated to encourage the laborers to spend their long winter evenings profitably. There were two of these shows in each season, in July and September. They began in 1850, and were kept up until the time of his death. Tents were pitched for receiving the productions of the cottagers' gardens, and the allotment-tenants received premiums for the best management of their pieces of ground. Besides the tents for the more special purposes of the show, there was always one assigned to a miscellaneous collection of specimens in natural history—animals, birds, reptiles, insects' nests, etc., with various specimens from the domestic arts and antiquities. This the professor called his "Marquee Museum." On one occasion the dimensions of the trunk of the great mammoth tree (Wellingtonia) were traced out on the lawn with a diagram, showing its size in comparison with other trees. There was much to gratify the eye; but sight-seeing is always wearisome, and Prof. Henslow alleviated the routine of the day, and gave an intellectual turn to the proceedings, by summoning as many of the company as chose to come to the museum, and delivering to them little lectures, or "lecturets," as he termed them. He would talk to the women about textile fabrics or domestic operations, and to the different groups on processes of manufacture, or local specimens of natural history, or the diseases of vegetation. Nor were amusements neglected; swings and poles were set up for gymnastic exercises, and foot-ball and other games were encouraged on the grounds. The scene was