Sculptor William Edmondson's Critter could make $50,000-150,000 at Christie's folk art sale later this month.

Edmondson (1874-1951) was an outsider artist who is celebrated as one of the most distinctive voices in American sculpture.

William Edmondson was the first black artist to be given a solo show at MoMA

He quit his job as a janitor in 1930, after hearing a message from God, and set up shop as a stonemason.

Initially he carved tombstones, but soon branched out into creating figures and animals.

In 1936 a group of art industry insiders discovered his work. In 1937 Edmondson was given a solo show at New York's MoMA - a first for a black artist.

Critter has been in the same family since its original owner acquired it in the 1940s. It's a well-known piece and so will appeal strongly to aficionados of Edmondson's work.

Edmondson's The Boxer sold for $785,000 in January, well above its $250,000 estimate.  

The success of that sale suggests the present lot could achieve a similar result.

Henry Darger's The Pictures of Some of the Most Desperate Fighters in the Glandelinian Armies is valued at $30,000-50,000.

Henry Darger's work was only discovered after his death

Darger (1892-1973) was another outsider artist, who also worked as a janitor.

He became famous after his death, when his 15,145 page manuscript In the Realms of the Unreal was discovered by his landlords - who happened to be artists themselves.

The extraordinary work of science fiction tells the story of a rebellion of child slaves (led by a group known as the Vivian Girls) from a nation called Abbieannia against a group of adults known as the Glandelinians.

The Glandelinians are represented as Confederate soldiers (Darger had a strong interest in the American civil war).

In addition to the text, Darger produced a series of highly accomplished paintings and drawings of scenes from the story.

The sale takes place in New York on September 20 and will also feature Benjamin Franklin's presentation sword.

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