Hodgkin collaborated with Joseph Jackson Lister, who in 1830 enunciated design principles for the achromatic microscope. By that time Hodgkin and Lister had already published research on tissue samples, based on observations made with Lister's innovative microscope, in particular on the "globule hypothesis" of the time which was held in particular by Henri Milne Edwards. They denied the existence of globules in tissue; Ernst Heinrich Weber in 1830 contradicted them, and the debate continued for a decade. For a while microscopy suffered in its reputation, but by 1840 histology was a recognised discipline, and in time the view of Hodgkin and Lister that "globules" were optical artefacts became accepted. The 1827 paper they published has been called "the foundation of modern histology".