E. Morris Miller's Australian Literature from its Beginnings to 1935 (1940): 728-729 comments: 'The topography of The Desert Horizon, 1923, and its sequel, Daimon, 1925, covers the far north-west of Western Australia, with contrasting changes to Perth and its environs. These novels, written in narrative form, are a psychological study of the influence of wide silent spaces upon human contacts. Detailing in The Desert Horizon how Martin O'Brien from childhood came under the spell of the desert lands and their far-flung horizons. Watson makes of him a man at one with their solitude. He cannot cut himself apart. After marriage at Perth with the daughter of a newly-arrived immigrant, he sets himself the task of winning a station whose boundaries are the desert's limits. The tragic story of his married life is realistically recorded in Daimon. The wife, a city girl, bravely struggles to adapt herself to lands lying empty under the stars. She is afflicted by a morbid consciousness of unseen ghostly presences to which she reacts as though they were the dispensations of the devil. The husband, attuned to his environment through interest and work, fails to grasp the impending alienation of his partner in life, who craves for sex companionship. The toll of the desert upon white womanhood in Watson's novels was to be contrasted later in Katherine Susannah Pritchard's Coonardoo with the toll exacted upon white men who lived under the constant solicitation of attractive black women. In sheer desperation Martin yields to his wife's desire; he gets rid of his station and becomes a wheat farmer by the sea. But the call of the desert is in his blood, even in his middle 'sixties. He goes back and loses himself in the unknown. In the end his wife seeks him, and her wanderings have their counterpart in the desolation of 'Coonardoo'.
This is not the place to make a psychological valuation of Watson's viewpoint and conclusions. His general position is that city-bred women are not suitable for outback life in the far desert lands of Western Australia. His interpretation of the sex life of the woman he created in the character of Maggie O'Brien is open to serious question. But admitting its possibility, he has presented her relations with his paramour in an intensely dramatic pose, some portions of which might be regarded as a soliloquy in action. In these two novels he has daringly laid bare, in words carrying the spell of magic, what he believes to be the spiritual meaning of the desert. Others may assert that he has read into Australian conditions his own anthropological theories.'