I found this little jewel, buried in a discourse on monoculars vs binoculars.
"The lens is designed to capture the light from farther distances and amplify it, while the prism takes the image and inverts it. This is particularly important because when the light is amplified the image that is produced is upside down thanks to the lens shape."
"The lens is designed to capture the light from farther distances and amplify it, while the prism takes the image and inverts it. This is particularly important because when the light is amplified the image that is produced is upside down thanks to the lens shape."