Anyone who ever crossed the English Channel by boat -- I include Julius Caesar, Duke William of Normandy and myself among the host -- could not possibly help having wistful and nauseated thoughts about the dire need for a tunnel beneath those waters, and, in fact, during the past century the dream has been sporadically carried right onto the draftsman's board. So far, no tunnel.

But in "tunnel war," a marvelously detailed and suspenseful fiction, author Joe Poyer presents us the dream well on its way to fulfillment. The year is 1911, and with the thunderheads of the First World War just over the horizon, a British-French consortium is backing the construction of a railroad tunnel under the channel -- one team starting from the British coast, one from the French and a happy juncture in the making.

Imperial Germany, visions of Lebensraum dancing in it head, views these proceedings with foreboding. War-plans with every minute plotted are predicted on an inevitable British-French military alliance, but an alliance hampered by the difficulties of transporting British troops over the Channel. Railroading them under the Channel is a different matter altogether, nicht wahr ? Something must about it. But what?

The answer, it turns out, lies in that huge muster of Irish workhands toiling on the British end of the tunnel, now several miles toward its goal. Among them are a fair number of rabid Fenians, those progenitors of the Provisional I.R.A., ready to strike any blow against bloody Britain. Willing tools, they can be organized to destroy the tunnel before it inches its way to completion.

The high drama implicit in this is made explicit and personal through the author's shifting of focus back and forth among three pivotal characters: James Bannerman, designer and engineer of the works: Eric von Dorn, German military attache who plots the tunnel's destruction from a London office; and Michael Conningham, an exiled Fenian agent, now a sort of perambulating time-bomb who has secretly slipped back into England to avenge the murder of his sister. She, unknown to him, had been the line of communication between von Dorn and his Irish saboteurs and had second thoughts about her role just a little too late.

To further spice this witch's brew, Bannerman is locked between conflicting British principals, some of whom reflect as much antipathy to his slow and careful engineering procedures as Kaiser Wilhelm does to the whole project, and von Dorn walks a political tightrope -- a mile high and no net below -- between contending forces in the German overlordship, one as bitterly determined against any policy of sabotage as the other is for it. It is only Conningham, a rampaging bull in this International china shop, who can afford single-mindedly to pursue his goal, the destruction of his sister's killer, no more, no less. But even he in the course of his vendetta emerges vividly as a man agonized by complexities within himself that he must struggle to understand.

Most happily for the reader, much of the narrative takes place right inside those tunnel works on the outskirts of Dover, and here the author is at his best, convincing in his expertise and adept at having us share the brutally difficult and dangerous experience of tunneling deep under the sea through uncertain rock. Between this experience and the thrust and counterthrust of our protagonists at their murderous political game there is no short-weighting of suspense from start to finish of what is quite a hefty book.

If Poyer does let the side down between times, it is only when it comes to dealing with Bannerman's chief ally in the British superstructure, Winston Chruchill, First Lord of the Admiralty and a good chap to have on your side when push comes to shove. There are several early scenes where we are not only invited to enter the prescence of Churchill but, in a manner of speaking, to cozy up to him and here, through wooden dialogue and terribly reverent description which is sometimes so bad as to be funny, we are given the impression that the author is simultaneously working his typewriter with one hand while tugging his forelock with the other. Not only the story, but Churchill, deserved better than that.

Still, this does not weigh too heavily against the merits of the book as a whole. Let it be said that Poyer has taken the hitherto not very notable year 1911 and to put it on record in bright red numerals.