" The main point to be attended in burning with oil is, to burn up all the petroleum. I have not seen any burner that made a perfect combustion of all the oil that went into the arch ; that is, small particles of oil would fall upon the ground in the form of sparks, and there form a cake as hard as glass when cold. This, I believe, is wasted fuel ; and when this can be overcome there will be a great saving in the fuel used. My foreman is now working and experimenting on a burner of his own construction, and I am almost convinced in my own mind that he has struck the key-note of the problem.
"The steam used by us came from our engine-boilers some 60o feet distant and required considerable super-heating; but where a boiler is near the kiln I think super-heating unneces sary. For a ten-arch kiln it would require about a ten-horse power boiler. This could be moved along the shed from kiln to kiln as required.
" I have now given you my experience in the use of fuel oil.
" The conclusion I draw from its successful use under the dryers is that it makes a steady heat, enabling us to regulate its degree of intensity from the time the brick or tile go into the houses green until they come out dry. There is no smoke or soot to clog the flues, and the steam continually blowing into the furnace gives us at all times an excellent draft. Two men, one at night and one in the day-time, can attend to the drying, while with other fuel it takes from four to five men to do the same work. Two men can easily dry 200,000 brick in 24 hours just as well as they can 50,000.
" As to the burning of brick I can only speak of our own clay—a very difficult clay to burn right. From the time we start to burn until the finish we must continually force our fires. We only dry off twelve hours. With wood and coal it required much labor and constant care, but with oil and careful atten tion we can maintain a steady heat at any required degree, and you can manipulate it in such a manner as to give any part of the arch the heat required.
"The kiln never chokes, and cold spots are unheard-of things. You can hold your fires at any point. On one of three kilns we held the fires on the head in the face of one of the severest storms that has blown over Chicago for years—a gale that lasted eighteen hours—and that head was so hot you could not touch it with your hand.
"The oil which we use is obtained from the great and inex haustible fields of Lima, 0.
"It costs, with wood and coal, from 8o cents to $1.25 per thousand to burn my brick ; with crude oil it costs 40 cents per thousand. I have been using four brick-benches, and I
am sure I could use six brick-benches. There is a great sav ing in the labor required to fire the kiln, and are well burned throughout.
" The steam atomizes the oil, or it should do so.
"To begin, build a little wood fire to start the flame, and put one burner in each end of the arches of 27 feet in length, and it is possible to properly fire an arch 50 feet long. Use 4o pounds pressure of steam. There is no difference in the color of brick burned with oil as compared with those burned with wood or coal.
"Use oil stored in a tank placed higher than the burners, and use a cock to gauge the amount of oil for the burners." Mr. S. P. Crafts said, at the Third Annual Convention of the National Association of Brickmakers : " One cord of beech wood, worth $4, contains 17,065,000 heat units ; one ton of bituminous coal, at $4, contains 31,227, 000 heat units ; four barrels of fuel oil, 40 gallons each, at $1 per barrel at 6 pounds to the gallon, gives us 20,160,000 heat units.
" Here, then, we have data based on the cost and heat values for Southern New England, the variation from which will not be large for any of the brick manufacturing centres in that re gion, in which I include the Hudson river, New Jersey, etc.
"Now, which fuel shall we use? The greatest cost for labor in burning and the least cost for fitting up is with wood, but it involves the largest cost for fuel. The maximum cost for fitting up and the minimum cost for labor in burning is with coal, but with the least cost for fuel if all the heat which it con tains can be utilized. With oil the cost of fitting up is more than with wood, but less than with coal. The cost of burning with oil is less than with wood but more than with coal, unless a much greater per cent. of the heat of the oil can be utilized than that of coal. Now it is claimed that all the heat there is in the oil can be obtained, at least 19,000 out of the 20,200 units, and that with coal but 8,000 or 8,50o out of the 14,300 units. These are claimed as proportions in the pound weights of the two fuels. When we consider the cost, they more nearly approach each other. 12 pounds of oil cost 5 cents, and 12 pounds of coal cost 21 cents ; therefore to get at the relative values we must estimate the work of 12 pounds of oil and the work of 28 pounds of coal ; 12 pounds of oil at 19,000 heat units gives 228,000 heat units as against 224,000 at 8,000 or 238,000 at 8,500.