What is there to say about chalk and mathematicians? Much of what there is, is said in this paper:
“Chalk: Materials and concepts in mathematics research,” Michael J. Barany [pictured here] Donald MacKenzie, in: C. Coopmans, M. Lynch, J. Vertesi and S. Woolgar (Eds) Representation in Scientific Practice Revisited, 2014, pp. 107–130 (Cambridge, MA: The MIT Press).The authors explain:
“Today, chalk and blackboards are ubiquitous in mathematics education and research. Chalk figures prominently in the imaginations and daily routines of most mathematicians….
“This chapter reports a series of ethnographic findings centered on the theme of chalk and blackboards as a way of illustrating the distinctive modes of inscription underlying mathematical research. Chalk, here, functions both as a metaphor and as a literal device in the construction and circulation of new concepts. We begin, after a brief review of extant literature, by describing the quotidian contexts of such work. We then explore the blackboard as a site of mathematical practice before finally expanding on its metaphorical and allusive significance in other forms of research.”