Sergey
== Description == '''Sphygmograms, Figs. 1–4''', matching the illustration on H. P. Blavatsky's Scrapbooks, volume 12, page 220, item 2. Complete group of four traces and all four original figure labels, from John E. Purdon's article Sphygmograms Taken During the Occurrence of Psychical Phenomena. The group is retained as one composition. The artist and engraver are not established here. This is a separate scanned impression; the identity of the physical copy used for the al...
