162 GEOLOGY OF ILLINOIS. 



Some geologists reckon a ton of well manufactured prat fuel as equal 

 to a cord of dry hickory wood. If this is true, the Cat-tail is indeed a 

 valuable deposit. I sat by a x>eat fire several frosty evenings, while 

 making my investigations in this part of the county. The fuel certainly 

 made a cheerful fire. It was burnt in a grate ; made little smoke ; left 

 little ash, and that light and white; there was no unpleasant smell, and 

 a bright flame was given out. It consumed, however, rather rapidly, 

 and as a generator of heat is not equal to the better varieties of coal, 

 or the harder varieties of dry wood. 



And yet, after all this apparent fair showing, some caution ought to 

 be exercised in the investment of money in this new enterprise. The 

 great labor of handling the raw material must ever make the cost of 

 manufacturing peat bricks a considerable item of expense. The Eock 

 Island coal fields are at no great distance, and for many years will 

 cheaply furnish a good article of Illinois coal. The cost of peat ma- 

 chines is quite an item, and experience may encounter unexpected dif- 

 ficulties as further progress is made in the work. I simply throw this 

 out as a doubt in my well-grounded faith in the final and complete suc- 

 cess of manufacturing crude peat into a cheap and valuable fuel. For 

 coking purposes, and for the working of iron and steel, it is said to 

 furnish a heating material more valuable than any now in use. 



The principle of manufacturing the fuel, now being applied in the Cat- 

 tail mills, is essentially that of WEBER. The crude peat is ground by 

 cutting arms, revolving in a strong box, between fixed arms. When 

 the texture or fiber is destroyed, it is molded into convenient sized 

 blocks; some of the water is squeezed out ; it is then dried a few days 

 or weeks in the sun , and eventually is cribbed like Indian corn in cov- 

 ered narrow plank cribs. Condensation is chiefly effected by a destruc- 

 tion of the fibrous texture, permitting the peat, when it dries, to con- 

 tract into a more solid form. Compressed peat, or peat made by an 

 attempt to press or squeeze the water out, no matter how powerfully the 

 pressure is applied, will not succeed in making the pressed material 

 either dry or solid. Good peat is very elastic. When the pressure is re- 

 moved it returns to nearly its original volume. The partial closeness 

 of texture given to the outside hinders the drying process. Actual ex- 

 periments have taught the manufacturers this truth, and they have 

 abandoned the idea of pressing the water out by mechanical means. 



A cord of wet peat, by the natural process of drying, shrinks to one- 

 third or one-fourth its original size. Condensed into the solidity of ordi- 

 nary coal it shrinks much more. This loss of bulk and weight is caused 

 by the evaporation or loss of the water contained in the peat. The great 

 desideratum is to get rid of this large amount of water as economically 

 and with as little handling as possible. New processes of manufacture, 



