INTERESTING observations have been made recently on the Cologne-Minden Road, Prussia, on the rusting of iron rails. A pile of rails of odd lengths were laid on sleepers over a bed of gravel early in 1870, and remained undisturbed until the fall of 1877, there being no use for them. It was then found that they were covered with a layer of rust 0.12 inch thick, which had to be removed by striking the rail with a hammer. The cleaned rail weighed only 398.2 lbs., while its original weight was 419.1 lbs., showing that 5 per cent. of the rail had been destroyed by rust, which covered the rail quite uniformly. This confirms the observation often made, that rails stacked away are much more liable to rust than those laid down in a track. According to _Le Fer_, at a meeting of directors of the German railroads held at Constance, the following information was furnished in regard to the relative value of the different methods of injecting ties: 1. Railroad from Hanover and Cologne to Minden. Pine ties injected with chloride of zinc; after 21 years the proportion of ties renewed was 21 per cent. Beech ties injected with creasote; after 22 years, 46 per cent. Oak ties injected with chloride of zinc; after 17 years, 20.7 per cent. Oak ties not injected; after 17 years, 49 per cent. The conditions were very favorable for experiment; the road bed was good, and permitted of easy desiccation. The unrenewed ties showed, on cutting, that they were in a condition of perfect health. 2. Railroad "Kaiser-Ferdinands-Nord." Oak ties not injected; after 12 years the proportion renewed was 74.48 per cent. Oak ties injected with chloride of zinc; after 7 years, 3.29 per cent. Oak ties injected with creasote; after 6 years, 0.09 per cent. Pine ties injected with chloride of zinc; after 17 years, 4.46 per cent. The annual official reports of the railroads of India place the length of railways there at 7,5511/2 miles, of which 4921/2 miles were completed during the year 1877, and 223 miles since the close of the year. There are 8061/2 miles of double track; 5,9123/4 miles are constructed on the 5 foot 6 inch gauge, and 1,6383/4 on narrower gauges. The capital outlay on the State lines amounted to L3,122,051, and on the guaranteed lines to L1,374,882, bringing the total capital expenditure, up to the end of October, as regards the State, and to the end of March last, as regards the guaranteed lines, to L113,144,541. The expenditure up to the end of the year may be taken in round numbers at L13,344,500. The revenue from all the open lines was L6,232,888, of which L6,091,532 were earned by the guaranteed lines, with a capital of L95,482,941, and L141,356 were earned by the State lines, on a capital expenditure of L17,661,600. The net receipts from the guaranteed lines exceeded the amount advanced for guaranteed interest by L1,454,591; the year previous there was a deficit of L216,517.