Of late years rockets have fallen into disrepute everywhere, owing to radical defects explained by Captain C. O. Browne, R.A.;[414] and their use is unlikely to be revived until the chemists make some unforeseen and astonishing discovery. CHAPTER XII GUNPOWDER THE oldest recipe for gunpowder is Roger Bacon’s. If the solution of his anagram which I have ventured to propose be accepted, the proportions of the ingredients in 100 parts were:— _Saltpetre._ _Charcoal._ _Sulphur._ 41.2 29.4 29.4 The French recipe of 1338 being incomplete (Table VIII.), the next complete recipe for gunpowder is that given in the MSS. of Dr. John Arderne of Newark, who began to practise as a surgeon before 1350:[415]— “Pernez _j._ _li._ de souffre vif; de charbones de saulx (i. weloghe) _ij._ _li._; de saltpetre _vj._ _li._ Si les fetez bien et sotelment moudre sur un pierre de marbre, puis bultez le poudre parmy vn sotille couer-chief; cest poudre vault à gettere pelottes de fer, ou de plom, ou d’areyne,[416] one vn instrument qe l’em appelle _gonne_.” This gives in 100 parts:- _Saltpetre._ _Charcoal._ _Sulphur._ 66.6´ 22.2´ 11.1´ The word _gonne_, in the sense of cannon, must have been commonly known during the last quarter of the fourteenth century; for Chaucer uses it with this meaning in the “Hous of Fame,” iii. 553, cir. 1380— “As swift as pelet out of gonne, Whan fyr is in the poudré ronne;” and Langley uses it with the same meaning in the C text of his “Vision of Piers Plowman,” xxi. 293, _cir._ 1393:— “Set bows of brake and brasene gonnes, And shoot out shot enough his sheltrums to blend.” Now the explanatory phrase, “qe l’em appelle gonne,” shows that _gonne_ was but little known when the above recipe was written. We may therefore date it at 1350. It will be observed that down to the word _marbre_, the recipe is a literal translation of a receipt for rocket composition given by Marcus Græcus.[417] Yet the two powders, although made of _nominally_ the same ingredients in the same proportions, did not produce the same effects when fired; for gunpowder will not propel a rocket, and rocket composition will not project a cannon-ball. The difference in their effects was probably due to the researches of Roger Bacon, who had discovered the importance of using pure saltpetre and of thoroughly incorporating the ingredients. It is improbable that Arderne’s recipe represents the powder used in the cannon of his time. Its proportions are so entirely out of keeping with those of the French powder of 1338 (Table VIII.) and those of Whitehorne’s powder of 1560 (Table VII.), that we may regard it as no more than a laboratory receipt. It needed but little experience to show how far short of perfection serpentine powder fell.