View of Duurstede Castle at Wijk bij Duurstede by Jan van Goyen https://www.rawpixel.com/image/14264438/view-duurstede-castle-wijk-bij-duurstede-jan-van-goyenFree Image from public domain licenseHydrotherapy: eight vignettes of different cures at Gräfenberg, Germany. Lithograph, ca. 1860. https://www.rawpixel.com/image/14005179/image-dogs-cartoon-faceFree Image from public domain license