ALS between William Hellyer and Alfred Swaine Taylor Forensic Science c1840

HELLYER, William Watts McNair (1815–1880). Autograph letter signed to Alfred Swaine Taylor, inviting him to lecture on poisons or on photogenic drawing, with Taylor’s autograph note of thanks on the verso and the original, black-sealed envelope addressed in his hand.
 
Royal Institution, January 20th, [c.1840s].
 
4 pp., written in black ink, a few rust spots, otherwise very good, with the original tatty envelope (addressed “Alfred Taylor Esq., Cambridge Terrace, Regent’s Park”) and black wax seal intact. 
 
Writing as Vice-President and Secretary of the Royal Institution, William Watts McNair Hellyer invites Dr Alfred Swaine Taylor (1806–1880) to deliver a lecture at the Institution, suggesting as possible topics “Poisons, or on Photogenic Drawing.” He notes that he would willingly obtain the permission of the Committee of Managers for such a lecture.
 
On the address-leaf, Taylor has written his own brief acknowledgement, thanking Hellyer “for your courtesy in sending me a ticket for the evening lectures at the Royal Institution.”
 
Hellyer was a lecturer and chemist best known for his early public experiments and writings on the chemistry of light and silver salts—subjects central to the new art of photography, then generally referred to as “photogenic drawing.” His invitation to Taylor gives an early reference to photography in connection with the Royal Institution’s lecture programme.
 
Alfred Swaine Taylor, Professor of Medical Jurisprudence at Guy’s Hospital and author of On Poisons (1848) and Elements of Medical Jurisprudence (1836), was the foremost forensic scientist of his day, frequently called to give expert testimony in major poisoning trials. His work combined chemistry, physiology, and law, and his scientific curiosity extended to photographic processes and chemical light reactions. It is rare to have anything written by Taylor, the father of forensic science.