Skulls with wings, angels, and I think those are burning candles. It looks like a bathtub up at the top but I expect that's meant to be a coffin.
A close-up of the image on this side of the monument. Grim Reapers and their pet on the left, a winged skeleton blowing a trumpet at the top and horrified Victorians on the right side.
Etienne-Gaspard Robertson was a physicist, balloonist and a stage magician who used "phantasmagoria," a display of optical effects and illusions, to perform ghost stories. He was definitely a showman.
My sweetie and I tried out our neighborhood Indian restaurant for lunch today. Mmmm excellent garlic naan and tandoori chicken. Later.