Polytechnic Association. 783 



Dr. P. H. Van der Weyde — I saw in Paterson sixteen horses, driven 

 by half a dozen men with whips, drawing a large locomotive up quite 

 a steep hill, and I saw one of these little steam carriages attached to 

 another locomotive of equal size, and drawing it up the same hill 

 apparently with great ease. The contrast was very striking. 



Mr. Dudley Blanchard — We are gradually perfecting the arts which 

 tend to the perfection of steam carriages ; and, perhaps, it will not be 

 long before we shall arrive at the point when they can be made profit- 

 ably for common roads ; but of that I have some doubt, for it seems 

 to me that the power necessary to run a steam carriage over a soft 

 surface like a meadow is too great for economy. It will certainly be 

 a losing operation for the first undertakers of the project. My idea 

 of a steam carriage would be to make the boiler only three or four 

 inches deep, and to heat it with kerosene lamps fitted into slides to 

 run under the boiler. I believe that kerosene will give more power 

 for a given weight than coal. I would have a water tank to prevent 

 the heat from reaching the carriage above, and under the boiler I 

 would have two small engines operating the opposite sides of a crank. 



Prof. J. Phin — The horse is the worst animal in the world to go 

 over soft ground, because his hoofs cannot expand ; but you can make 

 the wheels of the locomotive as broad as you please. 



Prof. J. S. Whitney — I have seen the two leading traction engines 

 in operation — that of Mr. Thompson and that of Messrs. Aveling & 

 Porter. That of Mr. Thompson had a horizontal boiler and India rub- 

 ber tires. Both that and the engine of Messrs. Aveling & Porter work 

 extremely well. I have seen them plow, with seven plows, a foot 

 furrow, and do it well, and if they could rely upon a uniform consist- 

 ency of the ground underneath, they would be very useful. But in 

 this experiment one of them came to an ant hill, and there it stopped 

 and took nearly half an hour to get it out. They will travel across 

 soft plowed ground without the slightest difficulty, and on a hard 

 road will draw heavy wagons or pass up a steep bank. There is very 

 little to choose between the two> excepting to adapt them to special 

 conditions and circumstances. Some of them have been sent to Cali- 

 fornia and some to Utah. I do not think they will work well in 

 either of those countries, because all through California and Utah you 

 will find the hole of the gopher and prairie dog, and no traction 

 engine could plow across those fields. In order to be used there the 

 roads must be made good, and upon a good hard road they may be 

 successful. 



Dr. J. W. Richards — Mr. Baxter, the inventor of a boiler, has 



