2l6 KANSAS CITY REVIEW OF SCIENCE. 
wide, and perhaps twelve feet wide, coal above, below, and on both sides, glist- 
ening from our little lamps like black diamonds, and generally constituting a 
self-supporting roof. We penetrated in a straight shute 1400 feet, finding open- 
ings to the right and left, with occasional doors to regulate the draft of air which 
is supplied by fans on the outside driven by steam-power. Turning to the left 
some fifty feet, we found what appeared to be a small engine with a horizonta 
cylinder, made so as to drag along the ground, and working a drill horizontally^ 
The machine is really operated by compressed air forced into the mine through 
iron, pipes, which are connected with the machine by fl^exible rubber tubes. 
This machine is placed at the end of the tunnel and is moved by hand from 
one side to the other at the bottom, and by its effective action cuts to pieces a 
thin layer of coal under the great mass at the end of the tunnel ; two holes, 
twelve feet apart, near the top of the mine, are bored and cartridges inserted, 
and the mass of coal at the end of the passage way is blown off, several tons at 
a blast; quite an improvement on the old pick. Everything is systematized 
and moves like clock-work. 
Friday, May i8th, 4 o'clock P. M., finds us at Trinidad, the guests of its 
enterprising and hospitable citizens. With an elegant array of carriages we were 
met at the depot and driven over the city, and those who wished went to the 
Engle coal mine, three and a half miles away. At the mouth of the mine, at the 
west and south, we found a comfortable little mining town of some five hundred 
inhabitants, representing the usual nationalities. The coal beds, three in number, 
usually crop out near ravines, are easy of access, and are naturally drained. The 
beds are horizontal, no shafting or hoisting is* necessary, there is no dampness or 
bad air, as in most mines. These veins are parallel, varying in thickness from 
six to fourteen feet. The middle one is worked the most ; the roof of this is 
light-colored sandstone, and sufficiently strong to sustain itself, consequently 
saving all expense in blocking. Never before have I seen such a rare combina- 
tion of circumstances to produce first-class coal with so little labor, so little incon- 
venience to health and life to work the same. We notice here the mouths of two 
other tunnels, one opening into a mountain on the north and the other into a 
mountain on the east, both the mountains joined together at the base. The 
north tunnel runs clear through the mountain and also connects with the east 
tunnel. The magnitude of the work may be realized when it is understood 
that there are twenty- six miles of underground railway in this mine. 
Two hundred and seventy men and boys are here employed, and the 
amount of coal produced each day is one thousand tons ; its cost of produc- 
tion is sixty-two and a half cents per ton ; this includes interest on investment, 
wear and tear of machinery, weighers' and superintendent's salary. Coal sells 
at the mine at one dollar and a half per ton, leaving eighty seven and a half cents 
profit. On one thousand tons, the product of this mine per day, yields $875, or 
$319,375 per year, a very fair profit. Coke sells here at $5 per ton, though 
formerly brought from Pittsburgh at $25 per ton. To produce coke costs $2 per 
ton, leaving a profit of $3 per ton ; two hundred and fifty ovens will produce 
