HEAT OR CALORIC. 



103 



measure of water converted into aqueoils vapor, will, by its conden- 

 sation, raise about nine measures of water in the liquid form, one 

 hundred degrees." 



14. EXPLOSIVE POWER OF STEAM. 



" If a small glass bulb, hermetically sealed, 

 while containing a small quantity of water, be 

 suspended by a wire over a lamp flame, an 

 explosion soon follows, with a violence and 

 noise which is surprising, when contrasted 

 with the quantity of water, by which it is oc- 

 casioned. 



" In order to understand this, suppose that 

 the bulb were, in the first instance, merely fill- 

 ed with steam, without any water in the 

 liquid form. In that case the effort of the 

 steam to enlarge itself, would be nearly in di- 

 rect arithmetical proportion to the tempera- 

 ture ; but when water is present in the liquid 

 form, while the expansive power of the steam, 

 previously in existence, is thus increased, more steam is generated, 

 with a like increased power of expansion. It follows, that the in- 

 crements of heat being in arithmetical proportion, the explosive power 

 of the confined vapor will increase geometrically, being actually 

 doubled, as often as the temperature is augmented, somewhat less 

 than forty degrees of Fahr." 



Miscellaneous uses of steam.* 



1. For warming apartments, especially large manufactories. 

 There is no danger from fire ; the boiler may be even in another 

 room, and as the steam is transmitted in tubes, it is thus condensed 

 and gives out its heat. 



" Every cubic foot in the boiler is equal to heating two thousand 

 feet of space to an average temperature of 70 or 80," and each 

 square foot of surface of steam pipe will warm two hundred cubic 

 feet of space. 



2. For drying muslins and calicoes and other goods. Either the 

 stuffs are hung up in rooms and dried by steam pipes giving a heat of 

 100 or 130, or they are made to pass around cylinders filled with 

 steam. Delicate colors, such as scarlet and crimson, formerly faded 

 by stove drying, are thus preserved from injury, although heated to 

 165, and the people are healthy, which was said not to have been 

 the fact when the rooms were warmed by stoves. 



Concisely mentioned before. 



