These so-called nurse balloons, at Fort Sill, Oklahoma, carried gas to inflate other balloons used to observe enemy movements.National Archives

The more one goes up and down the battle line, the more one is amazed at the vital part which science is playing …

There is no branch of science which is not being applied in this war. This was a most surprising fact to me. Take geology. I had heard that geologists were attached to the staff; but I had pictured them as mining engineers rather than as professors of the pure science. Imagine, then, my surprise when I found in one of the rooms at headquarters a world-famous geologist studying and marking areas on a geological map of Flanders. All this country through which the battle line passes has been studied with care by geologists for many decades, and Belgium and France have both published sets of maps showing all the geological details. On the professor’s table was a map of the district directly east of Ypres; he was coloring certain areas red and others various shades of blue. He was also marking certain points and drawing a few straight lines.

Naturally I asked what it all meant. One color meant, “Here it is safe to make dugouts”; another, “Here you will strike rock”; another, “Look out for quicksands”; and so forth. The points meant, “Dig for water.” I asked him why he did not use a divining-rod expert (only I said a “dowser,” as I was speaking real English). He laughed and said that unofficially he might do so. The straight lines meant, “Here you may make tunnels or burrow mines” …

In this war the “weather man,” the meteorologist, has come into his own. No one laughs at him now. His information is desired by the artillery officer who has to know the temperature of the air and its moisture content, the strength of the wind at different levels, and the like, in order that he may aim his guns. When the temperature is hovering about the freezing point, the staff wish to know if the improvised roads will be frozen sufficiently to permit the movement of guns or motor trucks. The captains of the air squadrons must know the condition of the atmosphere up to heights of 20,000 feet …

At the beginning of the war the value of meteorological prediction was not recognized by the Allies. Two incidents produced a sudden change. One morning the batteries were ordered to resume firing at the same range as on the previous afternoon; no change in elevation was made, and the shells began landing in their own front trenches, whereas the day before they had reached the enemy’s lines. Such is the effect of marked changes in the air. In the early days the British weather reports leaked into Germany; and one week every condition reported indicated that for a few days ahead the weather would be such as the Germans desired for the dispatch of zeppelins over England. The forecasters in London, however, did not, in their printed statements, tell all that they knew, and informed the Admiralty that a change was probable which would make the conditions favorable for attack on the zeppelins. The latter came, and found the British ready for them. From that time on the meteorologist came into favor …

Ever since gunpowder was introduced into warfare, chemistry has been recognized as the one science which was essential in preparations for war; but a new chapter was opened when the Germans introduced poisonous gases as an instrument of death, in place of bullets. This was at the second battle of Ypres [in the spring of 1915], in which the Canadian soldiers suffered so cruelly. The plan then followed was to transport to the front-line trenches steel cylinders containing the liquefied gases, level down the edge of the parapet toward the British forces, letting the nozzles project over the top, and then wait for a favorable wind.

Of course, as soon as the idea of the Germans in planning this hideous mode of warfare was recognized, it became comparatively easy to block it; the preparations could always be seen; then a bombardment could be set up which destroyed the tanks where they were, much to the distress of the Germans themselves. Consequently, the manner of using poisonous gases had to be altered; and the plan adopted was to take the shells in use with the big guns and fill them with the liquefied gases instead of with shrapnel. Special guns were devised for use at short range; and these so-called gas shells now form a most important feature of artillery.

The only protection against these gases is a mask which may be put on quickly, and which is so constructed mechanically that the man can breathe in and out without strangling. The part of the chemist was to determine what substance should be put in the passages through which the air is inhaled, so as to absorb the poisonous gases. The way in which the French and English chemists solved this problem—for it is solved—excites the admiration of the world; and the real scientific work done in connection with it is a great contribution to pure science.

When the moral question involved in this use of gas as a weapon in war was settled and the Allies determined also to adopt it, chemists were again appealed to. The result has been a study of hundreds upon hundreds of gases, their toxicity, their density, their liquefaction, and the ease of manufacture; and here again the purely scientific side of the subject will be of permanent value. The work is going on unceasingly. Chemists are attached to all the armies, and chemical laboratories are in operation; so that, if the Germans send over any new shells—and a certain proportion always fail to explode—they may be investigated instantly.

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