Ghost Signs and Wall Dogs

As part of my research for my new book Hidden History of Denver (to be released next week) I studied the unusual signs I’d seen painted directly on brick walls, not only in downtown Denver…but in other towns too. I wondered who had created these works of art. They were obviously talented individuals, but how did they work so high in the air? I found their lives and work really interesting, and felt they had to be included in the book.

Following is an excerpt:

They were called “wall dogs” because they worked on walls and worked like dogs. The derisive term did not appear to concern the men who were part artists, part daredevils and, most of all, part chemists. Instead, they let their work speak for itself. Some of it can still be seen on the streets of Denver to this day, a testament to the quality of the work.

During the late 1800s, sign painters mixed the paint by hand, using a complex and intricate balance of chemicals, color pigments and a white base, which contained high levels of lead. The shopkeeper may have asked the sign painter to help him design a message that would best portray the shop. Since many of the people were illiterate or did not speak the language, signs were particularly beneficial.

The price the wall dogs charged depended on the height of the building. The higher floors were considered more hazardous, even if the weather was good. Sometimes Mother Nature was not kind to the men as they swung from a rope attached to their waist at the top of the building, paint in one hand and a brush in the other. Some men used a hanging basket or trellis, but either way it was still very dangerous work. In effect, they had to be part gymnast and part artist.


There was one potentially devastating effect from a long career as a wall dog: lead poisoning caused by exposure to white paint. It permeated their skin and their eyes, crippled their hands and weakened their bodies as it slowly poisoned them. Their brains were affected, they lost the ability to hear and then the deadly paint affected their nervous system. It was not until one hundred years later that lead was discovered to be the culprit, a fact not known to the men as they mixed a lethal dose of lead, linseed oil and color pigments. Later in life, the afflicted men appeared drunk or otherwise impaired, but in reality they suffered from “painter colic.”

Over the years, as businesses changed hands, so did the signs. One sign was painted over another, but in the right light, both may be visible. These are often referred to as “ghost signs” because they seem to appear in certain lights and then disappear at other times. It is a strange phenomenon, and one can only imagine the level of lead paint that had to be used for the images to last more than 120 years.