Original sentence: The Wu jing zong yao (武经总要, "Collection of the Most Important Military Techniques") of 1044 CE contains three recipes for explosives that Joseph Needham considers to be the first "true gunpowder" recipes: two for use in incendiary bombs to be thrown by siege engines (48.5% saltpetre, 25.5% sulfur, 21.5% others; 50% saltpetre, 25% sulfur, 6.5% charcoal and 18.75% others) and one intended as fuel for poison smoke bombs (38.5% saltpetre, 19% sulfur, 6.4% charcoal and 35.85% others).The first written recipe for gunpowder in Europe is a recipe for pure black powder, set down by Roger Bacon in 1242 and later mentioned by him in 1252, 1257 and 1267 (Gartz2007).This is the earliest extant written recipe for pure black powder, without any additional ingredients, from anywhere in the world
Edited sentence: The Wu jing zong yao (武经总要, "Collection of the Most Important Military Techniques") of 1044 CE contains three recipes for saltpetre explosives: two for use in incendiary bombs to be thrown by siege engines (48.5% saltpetre, 25.5% sulfur, 21.5% others; 50% saltpetre, 25% sulfur, 6.5% charcoal and 18.75% others) and one intended as fuel for poison smoke bombs (38.5% saltpetre, 19% sulfur, 6.4% charcoal and 35.85% others).The first written recipe for gunpowder in Europe was set down by Roger Bacon in 1242 and was later mentioned by him in 1252, 1257 and 1267 (Gartz2007).The first written record of the composition of gunpowder from anywhere in the world is written in the Wu Ching Tsung Yao dated 1044, where several recipes of gunpowder bombs to be thrown or launched from trebuchets was described