John Dalton, born 250 years ago, illustrated his atomic theory using wooden spheres

The English chemist John Dalton, born 250 years ago, illustrated his atomic theory using wooden spheres (pictured), drilled with holes for pins that enabled them to be linked into clusters. But there are hazards to such mental props. By the 1880s, students were so familiar with the spheres that one (taught by prominent advocate of atomic theory Henry Enfield Roscoe) declared: “Atoms are round bits of wood invented by Mr Dalton.”
Nature 537, 32–33 (01 September 2016)

https://doi.org/10.1038/537032a