In days gone by, many publishers had a collection of drop cap letter images they used to start each chapter of the books they printed. Quite a few publishers used the same block-like drop cap images but this set includes a bit of fancy scrollwork to make the letters a bit taller and more interesting.
This set of fancy letters were all used in the 1881 book How a Little Boy Learned to Be Wise and Good. It was written by Helen Cross Knight (1814-1906). These images are most likely from the publisher Thomas Nelson and Sons.
This image is copyright free and in the public domain anywhere that extends copyrights 70 years after death or at least 120 years after publication when the original illustrator is unknown.