38 ANNUAL OF SCIENTIFIC DISCOVERY. 



In the " Journal of the Franklin Institute," for November, 1867, 

 at the close of an interesting letter on the opening of the Mt. Cenis 

 Railway, Mr. Coleman Sellers made the following remarks : " The 

 use of two outside rails, and one central adhesion rail, was pat- 

 ented many years ago by Mr. George Escol Sellers. Mr. Traut- 

 wine, the engineer of the Panama Railroad, advocated the use of 

 this plan across the Isthmus. The engines were so built ; but the 

 engineer who succeeded him concluded to cut down the road and 

 use common engines. An engine was run on this plan in New 

 York, weighing 1,100 Ibs., which was capable of drawing up a 

 grade 250 feet to the mile with ease. The plan on which they were 

 constructed was better than that at present used in Europe, as they 

 were so constructed that the whole weight of the train should act 

 in producing adhesion, so that the heavier the load the harder the 

 grip on the central rail. I speak of this invention because I think 

 it is due to America to say that it is purely American, and was 

 advocated and used so long ago that the patent has expired; so 

 that you can judge very well that we have precedence of any other 

 country in this case." 



CENTRAL PACIFIC RAILROAD. 



According to Mr. George E. Grey, as given in "Engineering," 

 the Central Pacific Railroad of California commences the ascent 

 of the foot hills of the Sierra Nevada Mountains 7 miles from 

 Sacramento (tide-water of the Pacific), and thence to the summit 

 of the mountain pass, 7,042 feet, and 105 miles distant, there is a 

 continuous series of heavy ascending grades and sharp curves. 

 The maximum gradients on this portion of the line are 1 in 45, 

 of which, however, there is less than 6 miles, and the sharpest 

 curves are 575 feet radius. The line is completed and in opera- 

 tion to within 12 miles of the summit, and the earthworks and 

 bridging are nearly completed for 50 miles eastward to the east- 

 ern base of the mountains. From the eastern base of the moun- 

 tains for about 575 miles, to Salt Lake, the construction is remark- 

 ably easy and cheap ; the line follows the valley of the Truckee 

 River down to the big bend, where the river turns abruptly to the 

 north, and from there to the valley of the Humboldt River nearly 

 to its source, thence to Salt Lake, and the initial point of meeting the 

 Union Pacific Railroad from the east. The tunnelling is not of 

 any great extent, and the material pierced is generally of such a 

 character as not to require lining. The longest tunnel on the line 

 is at the summit of the Sierra Nevada, and will extend 1,658 -feet 

 through a very hard, tough granite. Nitre-glycerine is used for 

 blasting instead of powder, with rapid progress. All the other 

 tunnels are completed. 



NEW RAILWAY INVENTION. 



At the Paris Exposition a Russian engineer exhibited an inven- 

 tion whose object is to save the power gained in a descent, now- 

 lost in the friction of the brakes, with wear and tear, and use it 

 in the ascent. To effect this he attached two very heavy ily- 



