MEMOIR OF DANIEL TREADWELL. 



4(»;; 



powers of engines of different dimensions and forms of construction; the compara- 

 tive power of the same engines using steam of a given elastic force when running 



different velocities; the quantity of wood required to produce a gi\ 



pow 



the resistance of the load when passing upon a horizontal plane, and upon ascent* ol 

 different inclinations, and likewise the effect of the curves of the railway in increasing 

 the resistance; and any other facts important to the constructive arran ement or 



itions were made the 



management of railroads 



gines. These invest ig 



subject of an elaborate report, in March, 1837, which will be found in Appendix II. 



In 1838, Professor Treadwell was appointed by the Secretary of the Treasury of 

 the United States, together with Dr. Jacob Bigelow, Alfred Crccnou h, and William 

 Sturgis, on a commission for the purpose of superintending the experiments in 

 relation to lights in light-houses. But this appointment was declined. 



Professor Treadwell still retained his connection with the Huston Ihmp and 



Cordage Company, which grew out of the successful operation of his machines; lie 



was its agent for conducting a large business in spinning the hemp, in manufactur- 

 ing cordage, and in constructing machines for the Government, and for many of 

 the large manufactories. Indeed, it was the income from the e sources that enabled 

 him to accept the Rumford Professorship, from the funds of which he received but 

 about eight hundred dollars a year. 



In 1840 he had already been considering the practicability of constructing 



of greater strength, and consequently of greater calibre, than 



com 



mon use. Count Rumford had long before turned h 



d 



tion, but his experiments were limited to the use of cast iron, modified by a new 

 method of casting by which its tenacity was very much increased. The thoughts 

 and labors of the Rumford Professor were destined from this time to be directed to 

 the same subject for the greater part of his active life. He had by long experience 

 in the manufacture of machinery learned the properties of metals ; he had studied 

 the forces to which they are subjected when used as materials for cannon, and saw 

 the advantages to be obtained by the substitution of wrought iron and steel for 



bronze and cast iron. 



In 1845 he published "A Short Account of an Improved Cannon."* The fol- 

 lowing extracts will show the course of reasoning which led to the invention of the 



* This account was reprinted in 1865. It was translated into French in 1843, with the title, "Notice suecmcte 

 sur un Canon Perfectionne et sur les Procedes me'chaniqnes employes a sa Fabrication, par Daniel TreadwelL Tra- 

 duction de M. Rieffel, Professeur de Sciences appliquees a TEcole d'Artillerie de Vincennes." Paris, 1848. 



