Across the Stream, Lamorna (c. 1924) possesses a wonderfully intimate sense of place. Birch returned repeatedly to the stream that winds through Lamorna Valley, following its course from the wooded valley towards Lamorna Cove. The subject held a particular fascination for him, and a number of important paintings explore different sections of the same water course, including The Stream at Lamorna (c. 1914), now in the collection of Touchstones Rochdale, and a very similiar composition Our Little Stream, Lamorna (1934), in the Royal Academy of Arts.

For Birch, the appeal of rivers and streams was inseparable from two of his lifelong passions: painting and fly fishing. Alfred Munnings recalled of his friend: “when he was not painting he was fishing. And when he was not fishing he was painting.” His expertise as a fisherman sharpened his observation of moving water, and this relationship between fishing and painting was noted in The Times, which described how Birch “saw it with the understanding of both artist and fisherman.”

That dual perspective is particularly evident here. The stream is not simply a picturesque element within the landscape; it is the central subject of the composition. Birch follows its constantly changing surface with extraordinary sensitivity, catching fragments of sky, foliage and sunlight in broken passages of blue, turquoise, silver and gold. The water draws the eye from the immediate foreground, beneath the sweeping fallen trunk, and onwards into the shaded reaches of the valley where we see a river-side cottage and meadows rising beyond. The fallen tree itself provides a striking natural frame, its long diagonal counterbalanced by the upright trunks and branches.

There is also a wonderful tension between the solidity of the woodland and the fluidity of the stream. Birch's vigorous impasto gives physical presence to bark, moss and tangled vegetation, while his lighter, more broken brushwork allows the surface of the water to flicker and dissolve. One senses the artist not merely looking at the stream, but knowing it intimately; its pools, currents, reflections and most importantly, the places where a fisherman might pause.

By the mid-1920s Birch was firmly established among Britain's leading landscape painters. He was elected an Associate of the Royal Academy in 1926, the same year in which his work was represented at the Venice Biennale. Across the Stream, Lamorna belongs to this mature period and demonstrates the confidence with which he could combine close observation with a richly expressive handling of paint and in so doing, convey his profound familiarity with the landscape he had made his home.