38 
3rd. Carbonic acid gas consists of 72 oz. of oxygen, and 28 
oz. of carbon per 100 oz. 
4th. Carbonated hydrogen gas is formed of (from 74 to 80, 
say) 77 oz. of carbon, and 23 oz. of hydrogen per 
100 oz. 
5th. Cokes proper for a furnace afford, we presume, from 70 
to 80 per cent, of carbon, say 75 oz. of carbon from 100 
oz. of cokes. 
These proportions granted, leave us data to infer that 35 
oz. of vapour, with the assistance of caloric from the furnace, 
will produce 29. 75 oz. of oxygen gas, and 5.25 oz. of hydrogen 
gas ; and this 29.75 oz. of oxygen gas to form carbonic acid 
gas, will take up, consume, or destroy nearly 11.6 oz. of 
carbon, or 14.5 oz. of cokes. The 5.25 oz. of hydrogen gas, 
to form carbonated hydrogen gas, will also take up or destroy 
17.6 oz. of carbon, or 22 oz. of cokes. Hence it appears 
the introduction of 35 oz. of vapour per minute will completely 
deprive the process of combustion going on in the furnace, 
of the aid of 36.5 oz. of cokes per minute, or 137 lb. per 
hour : a quantity which will equal a sixth, or a seventh part 
of the whole quantity of cokes used in a furnace, requiring a 
blast of 2000 cubic feet of air per minute. By pursuing a 
similar calculation, we shall find that the effects of vapour in 
winter will be about one-tenth of the preceding quantity, or 
13.7 lb. per hour loss of cokes will be the result. The great 
difference, therefore, in the produce of a blast furnace, in 
the different seasons of summer and winter may, we presume, 
with sufficient reason, be attributed to the great diflPerence in 
the destruction of carbon or cokes in the furnace, by the 
vapour admitted along with the air ; that difference appearing 
to be no less than 124 lb. of cokes per hour. Whether a 
proportionate difference is, or is not, found in the produce 
of a blast furnace, we refer to the experience of every iron 
master present. 
It remains for us to notice the effects of a water regulator 
