864 TiiAxsACTioys of the American Institute. 



sonably sufficient in quantity. As no probable amount of pressure 

 could destroy it by crusliing, the mere waste by friction and corro- 

 sion become the only considerations concerning its durability. 



It is believed, by the projector of these methods of constructing 

 railway tracks, that they are the simplest and strongest which can 

 well be devised and rendered practicable ; that they embrace all 

 essential principles favoring improvements, and that, taking into 

 account the aggregate cost of all materials for building a road, the 

 time of doing the work, and the expense of keeping all the parts in 

 good repair after completion, they will be found to be the cheapest, 

 the most mechanical and the most economical ; over and above all of 

 which are the paramount considerations of safety for rolling stock, 

 for property in transit, and for animal and human life. 



The subject of rails for railways occupied the attention of the 

 meeting after the reading of this paper ; and at the conclusion of the 

 discussion. Professor R. P. Stevens, who had just returned from the 

 region of the Oronoco, South America, was introduced to the meet- 

 ing, and remarked that he had been requested to give some of his 

 impressions of the tropics. The lirst and most striking impression 

 is this : That tropical countries are very poor ; poor in their soil, 

 and consequently the people are poor. That first impression was 

 more and more confirmed as he examined the country in detail ; and 

 the reason why it is so is apparent to any person who has studied the 

 geological characteristics of the soil. He ventured to say that, 

 taking one year with another, the crop of the western portion of our 

 country is more profitable than the richest sugar crop of the East 

 Indies. The crops, however, vary every other year. Our western 

 country is far richer, in vegetation, than the tropics. We have 

 erected a mill in the valley of Yurana, and our head lumberman, 

 who was from the State of Maine, thought that, within a range of 

 one hundred miles we would not have enough timber to last us one 

 year. In Indiana he had seen timber enough to last a mill there for 

 many years. The forests are so impenetrable that one cannot step 

 one foot out of the beaten path, but the growth of vegetation cannot 

 compare with our country. In the month of June we have a higher 

 growth than any other. 



Professor Stevens continued his remarks until the hour for closing, 

 when the association adjourned for one week. 



