I took out my watch and determined how long I could hold my breath without inhalation. By emptying my lungs very thoroughly, and then charging them very fully, I brought the time up to nearly a minute and a half. In this interval I might have been urged through more than half a mile of carbonic-acid gas with no injury and with little inconvenience to myself.
Dr. Tyndall concluded, firmly, "The problem of supplying fresh air to persons surrounded by an irrespirable atmosphere has been already solved by Mr. Fleuss and others."
Then there were even more disturbing objections. Could the defenders at the English end always be relied on as absolutely loyal Englishmen? The Field, without naming any names, wrote of "proof that in the United Kingdom itself ... there are numbers of daring and reckless persons" who, "to gain their sinister ends ... would not hesitate to sacrifice the independence of the country." Frankly, the paper feared possible acts of treachery in the tunnel by "a handful of unprincipled desperadoes." And the Spectator, visualizing the thing in more detail, suggested that its readers "consider ... the danger of treachery ... the rush on the tunnel being made by Irish Republicans in league with the French, while the wires of the telegraph were cut, and all swift communications between Dover and London suddenly suspended." Taking all the risks of the tunnel into account, the Spectator said it could not bring itself to believe that "even in this age, with its mania for rapid riding and comfortable locomotion, such a project will be tolerated." The Sunday Times, for its part, pointed out that, as things stood, "the silver streak is a greater bar to the movements of Nihilists [and] Internationalists ... than is generally believed." But, it added, "with several trains a day between Paris and London, we should have an amount of fraternising between the discontented denizens of the great cities of both countries, which would yield very unsatisfactory results on this side of the Channel."
Meetings and debates to discuss the tunnel menace were held all over England, and even at a meeting of so progressive an organization as the Balloon Society of Great Britain, which was held in the lecture room of the Royal Aquarium at Westminster, the subject was discussed with "some warmth of feeling ... on both sides." There was a wide circulation of sensational pamphlets, written in pseudohistorical style, that purported to chronicle the sudden downfall of England at the end of the nineteenth century through the existence of a Channel tunnel—Dover taken, the garrison butchered, the English end of the tunnel incessantly vomiting forth armed men, London invaded, and England enslaved—all of this in a few hours' time.
In contrast to these manifold cries of alarm among the English, it seems never to have occurred to anybody in France at the time seriously to suggest that if a tunnel were to be constructed, a hostile English force, supported by an English navy in control of the Channel sea, might suddenly seize the French entrance by surprise and use it as a bridgehead for a general invasion of France. A few French commentators did, however, remind the anti-tunnel forces in England that while the English had set hostile foot on French soil some two or three times in as many centuries—not to mention her having kept physical control over the port of Calais for over two hundred years following the Battle of Crécy—English soil had remained untouched by France. Most of the French newspapers appeared to be unable to fathom the cause of the whole tunnel commotion, which was generally put down to English eccentricity. Several French journals, surveying all the fulminations on the other side of the Channel, even took an attitude toward the English of a certain detached sympathy. One of the more interesting French commentaries on the uproar in England appeared in the Revue des Deux Mondes. In this article, the author expressed some doubt that British military men who denounced the dangers of the tunnel were really convinced of the reality of those dangers. For them to do so, he suggested, one would have to presuppose, on one side of the Channel, a "France again a conqueror with, at her head, a man gifted with ... an incredible depth in crime; a secret, an almost incredible diligence in preparation as in execution," and, on the other side, "a governor of Dover who would be an idiot or a traitor, a War Minister who would not possess the brain of a bird, a Foreign Minister who would allow himself to be deceived in doltish fashion." How could the French possibly assemble perhaps a thousand railway carriages in England without arousing the suspicions of British Intelligence? How could the vanguard of the French invaders get through the tunnel with all their required ammunition, horses, and supplies, and get them all unloaded in a few minutes—would this vanguard sally forth without biscuits? The author found no solution to these particular problems. Instead, he devoted himself to the larger issue:
The day the inauguration of the Submarine Tunnel will be celebrated, England will no longer be an island, and that is a stupendous event in the history of an island people.... Islanders have always considered themselves the favorites of Providence, which has undertaken to provide for their security and independence.... They congratulate themselves on their separation from the rest of the world by natural frontiers over which nobody can squabble. They feel that they hold their destiny in their own hands, and that the effect of the follies and crimes of others could not reach them.... Their character is affected by this. Like Great Britain, every Englishman is an island where it is not easy to land.
And the article asked, wonderingly, "What would an England that was not an island be?"
The deliberations of the scientific investigating committee appointed by the War Office and presided over by Sir Archibald Alison lasted from the latter part of February until the middle of May. In the committee's report of its findings to the War Office, the complexity and solemn nature of the questions laid before it were indicated by their mere classification and subclassification. Thus, the contingencies for rendering a Channel tunnel absolutely useless to an enemy were considered under the headings of:
I. Surprise from Within
II. Attack from Without
And the committee reported that it had considered measures to secure the tunnel against (I) under such subcategories as: