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Few would expect women to feature often in the literature on minerology from the 15th through the 19th centuries, the recorded history of science being what it is. Among the approximately 1500 scholars in a massive catalogue of authors of mineralogy texts from 1439 to 1919 complied by the independent scholar, Curtis P. Schuh, we count six women as primary entries and three others discussed secondarily. From the documents that Schuh left behind before his death, our database for this investigation, women wrote approximately 0.5% of the texts described. Only very unusual circumstances supported the life of a woman devoted to crystals in centuries past. 

Optically-active optoelectronic materials are of great interest for many applications, including chiral sensing and circularly polarized light emission. Traditionally, such applications have been enabled by synthetic strategies to design chiral organic semiconductors and conductors. Here, centrosymmetric tetrathiafulvalene (TTF) crystals are rendered chiral on the mesoscale by crystal twisting. During crystallization from the melt, helicoidal TTF fibers were observed to grow radially outwards from a nucleation centre as spherulites, twisting in concert about the growth direction. Because molecular crystals exhibit orientation-dependent refractive indices, periodic concentric bands associated with continually rotating crystal orientations were observed within the spherulites when imaged between crossed polarizers. Under certain conditions, concomitant crystal twisting and bending was observed, resulting in anomolous crystal optical behavior. X-ray diffraction measurements collected on different spherulite bands indicated no difference in the molecular packing between straight and twisted TTF crystals, as expected for microscopic twisting pitches between 20–200 μm. Mueller matrix imaging, however, revealed preferential absorption and refraction of left- or right-circularly polarized light in twisted crystals depending on the twist sense, either clockwise or counterclockwise, about the growth direction. Furthermore, hole mobilities of 2.0 ± 0.9 × 10 −6 cm 2 V −1 s −1 and 1.9 ± 0.8 × 10 −5 cm 2 V −1 s −1 were measured for straight and twisted TTF crystals deposited on organic field-effect transistor platforms, respectively, demonstrating that crystal twisting does not negatively impact charge transport in these systems. 

The concept of Eshelby untwisting, the effect of an axial screw dislocation driving an intrinsically twisted nanocrystal towards a straighter configuration more consistent with long–range translational symmetry, is introduced here. Force-field simulations of nanorods built from the enantiomorphous (space groups, P 3 1 21 and P 3 2 21) crystal structures of benzil (C 6 H 5 –C(O)–C(O)–C 6 H 5 ) were previously shown to twist in opposite directions, even in the absence of dislocations. Here, both right- and left-handed screw dislocations were introduced into benzil nanorods in silico . For rods built from the P 3 2 21 enantiomorph, dislocations with negative Burgers vectors increased the right-handed twisting already present in the intrinsically twisted structures without dislocations, whereas dislocations with positive Burgers vectors drove the twisted structure back towards a straight configuration, untwisting. In the dynamic simulations, the P 3 2 21 helicoid endowed with a positive Burgers vector ultimately twisted back through the straight configuration, until a helicoid of opposite sense from that of the starting structure, was obtained. The bearing of these observations on the propensity of small crystals to adopt non-polyhedral morphologies is discussed. 

The anthropologist and acclaimed essayist, Loren Eiseley, in the midst of recounting a vision in the conclusion of a draft of a 1960 composition, “Creativity and Modern Science,” invoked Charles Darwin as the essay’s animating spirit. Eiseley modified his draft the next year and published it in no less than three of his subsequent books. The most striking differences between his draft and published texts is the substitution of Darwin in the final moments of the narrative with Francis Bacon, a barrister and philosopher who died nearly two centuries before the famous biologist was born. Here, is crafted a rationale for this unlikely switch, to the extent that the intent of another can be uncovered, by closely reading Eiseley’s psychologically charged work. Eiseley’s own struggles as both a scientist and an artist, identities respectively epitomized by Darwin and Bacon, reveal how and why the writer permitted his foremost heroes to be substituted, one for the other.