MATILDA, MY DARLING. By Nigel Krauth. Franklin Watts. 222 pp. $15.95.

Matilda, My Darling, a first novel by Australian writer Nigel Krauth, and 1982 winner of the prestigious Australian Vogel Literary Award, is an ambitious mixture of fact and speculation, a kind of historical fantasy whose purpose is not so much to illuminate the past as to vilify the present. "I suppose," Krauth has said, a little portentously, "I am one of several new writers and film- makers determined to re-interpret the old white myths about Australia . . . to travel the outback tracks of the Australian consciousness and discover the humanity of the national image, instead of blindly accepting the plastic cut-out into which it has developed today." This is rather a lot to ask of any novel.

The book is set in the 1890s, a decade of considerable social and political unrest. It focuses on the conflict between big landowning pastoralists and unionized sheep-shearers in Queensland, a clash which Krauth claims not only bordered on civil war but was instrumental in the formation of two major Australian political forces in this century: rural establishment and unionized labor.

Into this historic melee ventures the somewhat anachronistic fictional figure of Hammond Niall, alias Clohesy, alias Laver, a private investigator hired by union representatives to investigate the suspicious drowning of a swagman (itinerant bushman) at a remote Queensland waterhole in 1895. Niall has a jarringly modern sensibility -- we meet him on the first page arguing with his wife in their new "status-symbol bathroom" -- and seems mainly intended to embody what Krauth describes as a "1980s vision coming to terms with 1890s events." Thus history is to be made "relevant and accessible" to us m moderns.

Also traveling to Winton, Queensland, on Niall's train is none other than one Andrew Barton ("Banjo") Paterson, famous Australian poet, author of, among other things, The Man From Snowy River. This is where Krauth draws on real history, for Paterson did in fact travel to Queensland in 1895 to visit his estranged fianc,ee, Sarah Riley. During Paterson's stay, two things happened: he was inspired to compose what is probably Australia's best-known song, "Waltzing Matilda," which tells the tale of the swagman whose death Niall is investigating; and his engagement to Sarah was broken off. However, to the outrage of the poet's descendants, Krauth has made of the historical Banjo Paterson a fictional character -- a vain, silly narcissistic character, as it happens -- in order to make part of his larger point about where the country started to go wrong back in the 1890s.

THE DOUBLE PLOT, tracing the overlapping fortunes of Niall and Paterson during the few weeks of their imagined sojourn in Winton, is an ingenious one. The very idea of seeing in "Waltzing Matilda" the germ of a colonial Victorian murder-mystery is enough to engage one's interest immediately. Why, then, does Matilda, My Darling so deeply fail to satisfy?

The real problem is the crippling weight of Krauth's literary pretensions. He himself has compared his technique to that of D.M. Thomas or E.L. Doctorow, describing it as "a process wherein a modern fictional slant on history allows that history to speak more clearly to the present." What this means in practice is that Krauth continually obtrudes his contemporary prejudices into the story in the most heavy-handed way. Thus "Niall was willing to start out on an investigation only because he believed he knew where it would lead. To the tiny bud of a canker. To the germ of a national epidemic." Indeed. Other metaphors of sickness abound, all more or less crude, such as my own favorite: "The town is about to vomit its entire guts onto the plate of the plain, thought Niall."

And what is the nature of this national sickness, so ominously foreshadowed in 1895? Krauth's grievances are not primarily political, despite the class conflict at the heart of the differences between pastoralists and unionists. He seems to view both camps with equal distaste. No, Krauth is out to beat the tired old horse of Australian materialism, Australian lack of spirituality, Australian hatred of dreams and ideals and all the things supposedly embodied by the unfortunate swagman. "Everybody killed him," is the conclusion. "Because (he) was something we weed out in this country. We call him Anarchy on the stations . . . but others around here call him Rebellion and New Thinking, and you might call him creativity or Individualism."

Such slogans have no place in a novel. Over- simplification aside, this kind of thinking plays havoc with Krauth's prose style. He is not incapable of developing strong characters and a racy plot, but too often vents his underlying feelings in murky, overheated rhetoric. "The afternoon was drunken and lurching in Elderslie Street. The blasting sun staggered in the sky, the roadway sprawled. . . An air of anticipation weighed on the street thick and nauseous. . ." and so on.

American readers interested in the literature of Australia's "dead heart," spiritual or otherwise, would be better advised to read Patrick White's