66 president's address — section b. 



rested on the discovery of a chemical fact, was Parry's trial with an 

 airblast, made only a couple of months before the publication of Besse- 

 mer's first patent of 1855. A horizontal system, or grid, of wrought- 

 iron pipes, connected with the blast, was placed in the bottom of a 

 reverberatory furnace, with a large number of wires stuck vertically 

 into the upper portion of the pipes. Then fireclay was tightly rammed 

 around the structure, so that, upon the withdrawal of the wires, the 

 clay bottom was left perforated by about 100 small holes, all accessible 

 to the blast. In this feature of bottom tuyeres even Bessemer was 

 thus anticipated here. After careful drying the furnace was heated 

 up and about one and a half tons of pig iron were run in, the blast 

 having been previously let into the tuyere system. An exceedingly 

 vigorous action shortly ensued, the bath greatly heating up, but, un- 

 fortunately, the metal broke through the side of the furnace, stopping 

 the experiment, and a repetition was not permitted. The merit lies in 

 the fact that the execution of the idea was predetermined and pre- 

 meditated, and the discovery of the increased, almost volcanic, action 

 of the metal was not the result of an accidental observation only, made 

 in some casual way. Together with the rise in temperature this action 

 was consequently discovered, by both Kelly and Parry, before Bessemer. 

 But their manner of materialising it in a proper mechanical form was 

 impracticable and crude. 



Bessemer' s Invention. — The next events in order now are Bessemer's 

 own inventions. These are so well known that I may avail myself 

 of the circumstance that the application of the pneumatic principle 

 to the manufacture of steel and wrought iron is really foreign to my 

 subject, and confine myself to a brief resume, virtually only the state- 

 ment of a few facts and dates, to note the march of time. The first 

 Bessemer patent was granted on October 17th, 1855, and stood for a 

 method of forcing currents of air or steam, or of air and steam, into 

 and among the particles of molten pig, &c., the metal so treated re- 

 taining the fluid state and being readily poured and run into moulds. 

 This patent applies to Bessemer's very earliest experiment, m which 

 the pig was melted down in a crucible, contained in a pot furnace, the 

 gases being introduced by means of a pipe inserted into the metal 

 from the outside. The description states that steam cools the metal, 

 but air causes a rapid increase of temperature, so that the metal passes 

 from a red to an intense white heat. This increase in temperatiu-e 

 typifies the main essence of the Bessemerising process. Subsequently 

 it remained the inventor's chief labor to perfect the mechanical side 

 of his invention to the fullest and most enduring extent. The second 

 patent, two months later (dated December 7th, 1855), already em- 

 braces all the essential detail features of the Bessemer process and its 

 practical execution in the form in which these have maintained their 

 vogue to the present day. Currents of air, or steam, are forced up 

 through the molten metal, contained in a suitable vessel, spherical 

 or egg-shaped, built of iron and lined with refractory matter (firebrick), 

 and which may be suspended on trunnions to allow of tilting, the 

 vessel being closed at the top, with the exception of an opening for the 



