Richard Watson

The development of the circular dividing engine in England is traced from Henry Hindley and Jesse Ramsden through the improvements introduced by Ramsden's successors to the self-acting engine of William Simms. Particular emphasis is given to the invention, evolution and transmission of the methods used to achieve accuracy in: dividing the wheel; ratching the teeth and matching them to the endless screw; and mounting the cutter. The procedures adopted by Ramsden and Troughton for correcting initial dividing marks are also described.     

Science in English encyclopædias, 1704–1875.—III

This note discusses lecture plates at the Hugo de Vries Laboratorium that may be relevant to Hugo de Vries's claim to have independently discovered Mendel's law of segregation. Dating when the plates were made is problematic.     

The celestial mechanics of Leibniz in the light of Newtonian criticism

By the middle of the nineteenth century science was developing into a profession demanding advanced training and devotion to research. American institutions, however, were still better suited to an earlier stage of popular science. Many of the difficulties and frustrations for would-be scientists created by the time lag in institutional change are illustrated in the career of Cleveland Abbe. In the fifteen years between 1856 and 1871 his attempts to become an astronomer touched upon many significant aspects of American science as a profession, including the American observatory movement, the creation of graduate education, government support for science, and the tension between the joint goals of the increase and the diffusion of knowledge.