Sir,--I was unwilling to write you until I had made a little trial of the Herland engine. It has been at work about ten days, and works exceedingly well; everyone who has seen it is satisfied that it is the best engine ever erected. It goes more smoothly than any engine I ever saw, and is very easy and regular in its stroke. It's a 33-inch cylinder, 10-1/2-feet stroke. We have driven it eighteen strokes per minute. In the middle, or about two-thirds of the stroke, it moved about 8 feet per second, with a matter in motion of 24 tons; and that weight returned thirty-six times in a minute, with 2 bushels of coal per hour. This of itself, without the friction, or load of water, is far more duty than ever was done before by an engine. I found that it required about 80 lbs. to the inch to work the engine the first twelve hours, going one-third expansive, twelve strokes per minute, 10-1/2-feet stroke, with 24 bushels of coal. The load of water was about 30,000. This was occasioned by the extreme friction, the plunger-pole being turned, and the plunger-case bored, to fit so nicely from end to end, that it was with great difficulty we could at all force the plunger-pole down to the bottom of the plunger-case. This is now in a great degree removed, and since we went to work we have thrown into the balance-box 4 tons of balance, and it would carry 3 tons more at this time. We must have carried that load in friction against the engine, therefore, if you calculate this, you will find it did an immense duty, going twelve strokes per minute, 10-1/2-feet stroke, with 2 bushels of coal per hour. The engine is now working regularly twelve strokes per minute, with 60 lbs. of steam, 10-1/2-feet stroke, three-quarters of the stroke expansive, and ends with the steam rather under atmosphere strong, with considerably within 2 bushels of coal per hour. I would drive her faster, but as the lift is hanging in the capstan rope under water, they are not willing to risk it. I have raised the steam to 120 lbs. to the inch, the joints and everything perfectly tight. I took the packing out of the stuffing box and examined it, and found that the heat had not at all injured it; the packing is perfectly tight, not a particle of steam is lost.