The Phosphates of America. 95 



The packing must be carefully attended to, the proper plan 

 being to commence Avith a few of the best fire-bricks at the bottom, 

 following this with a couple of feet of large, chemically clean,, 

 pure flints, and finishing up with large lumps of hard-burnt oven (not 

 gas) coke, the latter being not only an admirable absorbent, but 

 also extremely cheap and sufficiently light to obviate any danger 

 from lateral pressure. Into the exit-pipe are fitted very small 

 glass windows, through which it will be satisfactory occasionally 

 to note that the escaping gases yield no red fumes by contact with 

 the air. A few feet above the tower is placed a cistern, which, by 

 means of a properly regulated tap, supplies the cold, absorbing 

 sulphuric acid of a strength equal to 62 B., and the great point 

 to be attained is the maintenance of such a perfect and equal dis- 

 tribution in the form of a drizzling rain that not a particle of 

 the ascending gases may escape its contact. A convenient sam- 

 pling arrangement is connected with the tank at the bottom, and 

 the nitrous vitriol is frequently tested by adding to a small sample 

 a quantity of very cold water, when, if the absorption has been 

 complete, large volumes of red fumes will be thrown off. The 

 liquid is pumped from' the tank to the Glover tower by means of 

 the " egg," as hereafter described. 



THE GLOVER TOWER. 



This remarkably ingenious and valuable addition to the sulphu- 

 ric-acid plant is named after its disinterested inventor, Mr. John 

 Glover, an English chemist, and is to be shortly but accurately de- 

 scribed as 



First. A most perfect, rapid, and economical concentrator of 

 chamber acid. 



Second. An absolute denitrator of the nitrous vitriol. 



Third. An adjunct sine qua non to the Gay Lussac tower. 



That it should still be far from universally used or even known 

 in this country is an extraordinary and regrettable fact, which 

 affords sufficient reason for here devoting a certain space to an ex- 

 position of its value. 



The erection of a Glover tower, while not a difficult matter,, 

 nevertheless requires very careful study, sound judgment and 

 considerable knowledge of the functions it is expected to fulfil. 



Occupying an intermediate position between the pyrites furnaces- 

 and the chambers, it receives the whole of the sulphurous and ni- 

 trous gases arising from the combustion. With a height of 30 feet 



