1860-1877 Great Trigonometrical Survey of India General Reports These are the 1860-1877 Great Trigonometrical Survey of India General Reports. Click to download. 1862 General Report on Operations of GTS of India during 1860-62 s (missing pages) Size: 784K 1863 General Report on Operations of GTS of India during1862-63 s Size: 2.5M 1864 General Report on Operations of GTS of India during 1863-64 s Size: 1.5M 1866 General Report on the GTS of India for 1864-65 s Size: 3.3M 1867 General Report on Operations of GTS of India during 1866-67 s Size: 7.5M 1868 General Report on Operations of GTS of India during 1867-68 s Size: 6.7M 1869 General Report on Operations of GTS of India during 1868-69 s Size: 5.4M 1870 Report on GTS of India during 1869-70 (5 Surveys) s Size: 916K 1871 General Report on Operations of GTS of India during 1870-71 s Size: 9.3M 1872 General Report on Operations of GTS of India during 1871-72 s Size: 9.9M 1873 General Report of Operations of GTS of India during 1872-73 s Size: 12M 1874 General Report on Operations of GTS of India during 1873-74 s Size: 12M 1876 General Report on Operations of GTS of India during 1874-75 s Size: 7.5M 1877 General Report on Operations of GTS of India during 1875-76 s Size: 9.3M 1878 General Report on Operations of GTS of India during 1876-77 s Size: 14M