“but take 7 parts of saltpetre, 5 of young hazel-wood, and 5 of sulphur,” &c.;
i.e. 1-2/5 sp., 1 char. and 1 sulph.
R. was the common contraction for recipe, and may be seen in Marcus Græcus’ first recipe (Berthelot’s text). Nov. Corul. could have presented no difficulty to Bacon’s correspondent, seeing that in the previous letter, Cap. X., Bacon had spoken of virgulti coryli. There he writes coryli: in his Opus Majus he wrote coruli (ii. 219, Bridges ed.).
The second anagram (in Greek, Roman, and Anglo-Saxon letters) seems to be a note to the first and need not detain us, since we have already got the names and proportions of the ingredients.
In deference to those readers who may reject the preceding attempts to read Bacon’s riddles, we now proceed to show, on grounds independent of the steganogram and anagram, that Bacon was in possession of an explosive.
The igneous bodies of which Bacon speaks fall into two classes. The first class are incendiaries. “Incendiaries,” he tells us, “may be made from saltpetre, or petroleum, or maltha,[372] or naphtha, mixed with other substances.... To these are allied Greek fire and many other incendiaries[373].... (Burning) maltha, if thrown upon an armed soldier, will cause his death.... It is difficult to extinguish, water being useless for this purpose.”[374]
But side by side with these passages we find descriptions of igneous compositions of a totally different kind. “There are other natural wonders. We can produce in the air sounds loud as thunder and flashes bright as lightning—nay, even surpassing the powers of nature. A small quantity of (a certain) composition, no bigger than one’s thumb, will give forth (on ignition) a deafening noise and a vivid flash.”[375] We have, too, the passage, already quoted, in the eleventh chapter, where he says that saltpetre and sulphur and something else give forth (on ignition) “a thundering noise and a vivid flash.”[376] Again: “Some compositions (when ignited) make an unbearable noise.... No other sound can be compared with it. Others produce flashes more fearful to behold than real lightning.... We may exemplify these effects with a child’s toy which contains within it a quantity of saltpetre (mixture) the size of one’s thumb. In the bursting of this bauble, made only of parchment, there are given forth a noise louder than the mutterings of thunder and a flash brighter than the brightest lightning.”[377] It will be evident on a moment’s consideration that the charge of this toy must have been an explosive. Had it been an incendiary, the paper would have taken fire long before the pressure of the gases generated by the combustion had increased sufficiently to burst the case, and there would have been no loud report.
The consequences of igniting these two classes of composition are described so clearly as to preclude all possible misunderstanding:—the incendiary burns fiercely, while the other mixture gives forth a bright flash and a loud noise. In the latter case, Bacon was describing an explosion, and, as he has elsewhere spoken of saltpetre, charcoal, and sulphur, the reasonable conclusion is that the explosive was gunpowder.
It has been said that the first of the foregoing passages—“there are other natural wonders,” &c.—describes a rocket. As everybody knows, a rocket in its flight makes a whizzing noise and is followed by a trail of heated gas and sparks. The whizzing noise can only be compared to thunder by a total disregard of fact, for no sound resembles thunder less. Does thunder whizz? The fiery trail can only be called a flash by an equal disregard of fact: it gives a continuous light. But if the rocket carries a bursting charge which explodes in mid-air, the explosion may, with venial exaggeration, be said to produce a flash like lightning and a noise like thunder. Bacon was alluding to a bursting charge consisting of an explosive, and that explosive was gunpowder.
Was Bacon aware of the projective force of gunpowder? There is nothing in his works (so far as I am acquainted with them) which suggests that he was. He knew that gunpowder exploded, and he believed that an army might be either actually blown up by it, or put to flight by the terror inspired by its explosion;[378] but he seems to have gone no further. He experimented, probably, with very small quantities of it; and the behaviour of gunpowder when fired in large quantities under pressure is so unlike its behaviour when fired in small quantities in the open air, that its projective force could neither have been predicted by abstract reasoning nor realised by even his powerful imagination.