84 On the Production of Steam from heated Iron. 
RESULTS. 
lst series. —Time reduced from 100’ ‘to 18” by the coat of earthy ma 
ter successively deposited from ths oz. of muddy water. 
2d series.—Hot water constant at 13.5” 
old water do. 0. 
3d serices.—Mean time for hot water 15.6’—coated metal red hob 
each time. 
Mean time for cold water 13.37’. ' 
Ratio of cold to hot 1 : 1.167. 
4th series.—Hot water constant at 12”. 
water constant at 10.5”. 
Ratio of cold to hot 1: 1.143. 
5th series.—Hot water constant at 13”. 
old water constant at 11.5”. 
Ratio of cold to hot 1: 1.130. 
6th series.—Mean time fur hot water 32.6”. 
Mean for cold water 26.2”. 
Ratio of cold to hot 1: 1.244. 
7th series.—Mean for hot water 23.6”. 
Mean for cold water 20.6”. 
Ratio of cold to hot 1: 1.145. 
8th series.—Mean for hot water 16.5”. 
Mean for cold water 15”. 
Ratio of cold to hot 1: 1.100. 
9th series.—Constant at 25” to the ounce. 
The first series represents the gradual diminution of time fi 
100 “down to 18” and shows that here the impurity suspended! 
the water, retarded vaporization more thari the depression of te 
perature could accelerate it. In the second series, the two effects 
came exactly counter-balanced and so remained through several 
periments more than are given in the table. 
Fourru COURSE, consisting of six series. 
~The sixth being intended to show the times required to evapo 
or to vaporize equal portions of water from the surface of iron wl 
er series ane designed to exhibit the relation in time, between 
