The Practical photographer; an illustrated monthly of technical photography (1904)
Boston [etc., Photo era publishing company] · leaf 90
Fig. 43. … Fig. 44. F.C.L. EXERCISE IN SHADOW MODIFICATION. In Fig. 44 the teeth have been nearly removed by scraper needle (Fig. 6 ), and the upper lip slightly lowered in position. The shadow under ihe lower lip is slightly modulated.
Photography
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.