90 



REPORT — 1842. 



If we examine the results of this table, it will be observedthat the deflec- 

 tion in the cold blast iron has not increased but rather decreased since June 

 1S38, an anomaly not easily accounted for, unless from some error in writing 

 down the figures 1-316, which — according to the progressive increase which 

 has been going forward since the commencement of the experiments — should 

 have been 1*306. On comparing the rate of increase of the deflection in 

 this table with Table XII. in my former Report, it will be seen that the 

 tendency downwards has been regular and progressive (with the above ex- 

 ception) up to the present date. In the hot blast iron it is also progressive, 

 the increase of deflection in four years being -082. 



It will be observed, that the state of the atmosphere has considerable in- 

 fluence upon the bars, an increase of temperature producing a correspond- 

 ing increase of deflection, and vice versa. 



Table II. 



Table of deflections, as exhibited with permanent weights of 392 lbs., sus- 

 pended from the centre of bars of cold and hot blast Coed-Talon iron, 

 cast to be one inch square, and left to determine the effect produced on 

 each bar after given intervals of time. 



Distance between supports 4 ft. 6 in. 



Results in the preceding table and the previous reports, showing the pro- 

 gressive and increased ratio of deflections, from the 23rd of June 1838 to 

 April 29th of the present year. 



