: 523 ] 
X. The Bakeeian Lecture. —Chemical Theory of Gunpowder . 
By H. Debus, Ph.D ., F.B.S. 
Received February 8,-—-Read February 23, 1882. 
Table of Contents. 
Introduction ... 
Discussion and explanation of tlie results of Noble and Abel’s experiments. 
Explanation of the chemical reactions which occur during the explosion of gunpowder ...... 
General equation representing the transformation of gunpowder during complete combustion. 
Calculation of the results obtained by Bunsen and Schischiloff, Linck, Kabolyi, and Noble 
and Abel. 
Calculation of the amount of gas and heat developed by the combustion of a quantity of powder 
containing 16 mols. of saltpetre, y atoms of carbon and z atoms of sulphur . 
Calculation of the relative energies of mixtures of saltpetre, carbon and sulphur in different 
proportions, and determination of the composition of the mixture which will develop the 
greatest energy . 
Summary of main results. 
According to Bellani, the English army used cannon at the Battle of Crecy in the 
year 1346. The correctness of this report has been doubted since English and French 
writers in their description of the battle do not mention the use of cannon. How¬ 
ever this may be, it is certain, that from the middle of the 14th century the applica¬ 
tion of powder to the purposes of the art of war became more and more general, until 
towards the close of the Middle Ages heavy ordnance was used by all European armies. 
The effect of this new application of gunpowder upon the civilisation of our race is 
usually considered to have been of the same importance as the invention of the art of 
printing or the discovery of America. And, although 536 years have passed away 
since the Battle of Crecy was fought, we have to this day no satisfactory account of 
the chemical reactions which occur during the combustion of gunpowder, no theory 
to enable us to determine the quantitative relations of the products of combustion 
d priori from the composition of the powder. The attempts, which have been made 
from time to time by eminent men to supply solutions of the problems indicated, have 
been, as is well known, unsuccessful. 
In the following pages I propose to describe a theory which explains in a satis¬ 
factory manner the chemical reactions which occur during and after the explosion, not 
only of a powder of normal composition, but, generally, of a mixture of x molecules of 
saltpetre, y atoms of carbon, and 2 atoms of sulphur. 
Pages 
523 
524-546 
546-559 
560 
561-569 
569-576 
576-590 
590-594 
