The attention paid to Jack Yeats every year during the Sotheby's and Christie's Irish art sales (both later this month) has tended to cause work by almost all other artists in the auctions to be overshadowed. In particular, Paul Henry's paintings, although a regular feature of such auctions, have not received much notice of late.

Like Yeats, Henry was a prolific artist - there were 10 of his pictures in last December's Irish art sale at Adam's and another one in the same company's sale at the end of this month, as well as eight in a Christie's sale and nine in that of Sotheby's - which has not necessarily assisted his posthumous reputation.

In addition, there is a similarity of theme and style in many of his works, much of which features white-washed cottages backed by blue-tinted mountains beneath a cloud-lined sky.

Paintings of this kind did much to define an image of Ireland during the early part of the century, and they came to be symbols of a newly-independent state. However, they also came to seem almost cliches of Irish imagery and, as such, were potentially damaging to perceptions of Paul Henry.

In addition, so effective have these landscapes been on creating an impression of the artist that his earlier work is not as well known as should be the case, even though paintings from Henry's Achill Island period now command higher prices. Since both Sotheby's and Christie's have one Achill picture each in their respective sales, these merit particular examination. Accompanied by his wife Grace, Henry travelled to the Co Mayo island in 1912 after returning from Paris, where he had read Synge's Riders to the Sea.

He spent the next seven years in Achill, where he produced a sequence of paintings in which the human figure predominates; this is one feature which distinguishes the Achill paintings from Henry's later work, in which the landscape is usually un-populated. The Christie's picture is typical in this respect. Lot 214, Digging Potatoes, Achill Island, Co. Mayo (estimate, £60,000-£100,000 sterling) was painted during the latter part of Henry's stay on the island and shows certain affinities with the pictures of French peasants produced the previous century by Millet.

In both instances, the toil of labour is celebrated without sentiment or condescension; Henry's work is the pictorial equivalent in this respect of Synge's plays. Similarly, Lot 301 in the Sotheby's sale, The Bog Workers (£200,000-£300,000), shows two workers building up a pile of peat.

Writing in the early 1950s of his time on Achill Island, Henry remarked: "I have yet to see people who worked so hard for so little gain. It meant incessant toil with the spade; ploughs were useless on most of these stony fields. There were no roads into the fields for carts and everything had to be carried in creels on the ponies' backs in storm and rain to the widely separated fields." The romanticism of Irish landscape which was to inform, if not infect, Paul Henry's later work is largely absent in his Achill paintings, which possess a sympathetic realism. This is one reason why they are especially valued; another Achill-period picture, The Potato Harvest, set a new record for the artist when it was sold for £104,000 by Adam's in Dublin in September 1996.

Then in June 1997 at Phillips of London £166,500 was paid for The Watcher, which was painted by Paul Henry on Achill circa 1914-1916. Given the estimates on the Sotheby's picture, this figure could be surpassed before the end of the month.