[For the Scientific American.] The many sad accidents which are occurring, almost daily, in our country, on railways, demand that some efficient means may be put in operation to check the great sacrifice of human lite on these roads, and the ruin of so much property. The railroad system is widely extending throughout our country, and except, in their plan and construction, we can insure safety to the passenger we shall only increasing the evil and trifling with human life. The fearful speed now attained on railroads adds to the risks now run by the passenger in case of meeting any obstruction, however slight, which would cause the wheel to fly the track. The exposed state of these roads makes them liable to injury, and the facility of producing a ruin is a strong temptation to the unprincipled highwayman. Before our railroad companies enter upon any new works of this kind, they should institute an inquiry whether there is any improved plan of railroad which combines safety of travel with economy of construction : any plan which would secure and insure the wheels from running off the rail under any degree oi velocity given the train: any plan which would be free from the common accidents, including collisions, which now occur on railroads; that will do away with, the necessity of road guards, signals, switches, and sueh-like attendance; and last, though not least, a plan which will not cost even a moiety of the sum now paid per mile on the present plan of railroads. In the name of a suffering community we wonld urge that these inquiries should be made, and if there is any practicable plan of railroads which promises this immunity from such evils, these companies are bound to avail themselves of it, and put an end to the sad record which now, almost daily blots the pages of our history. The undersigned can, with confidence, say that there is hope oi such an exemption from these evils, by the consummation and the perfecting of a plan ot railroad embracing all the requisites of safety to the traveller. The Pacific Railroad will be soon stretching its length* ened line across our country, and such securi- ty should be given its travel, that our people may reach its distant terminus in as many minutes as there are miles of distance. The locomotive engine which is to accomplish this desirable speed, is already perfected, and needs only the periecting of the rail upon which it is to travel,—this, as has been said before, is near its accomplishment. ROBERT MILLS, Engineer and Architect. Washington, D. C, 1853.