Here are the links for the OCR, text-only volumes of The Scientific American from Hathi Trust. To view the volumes in full-imagery mode, however, you’ll need to add the suffix ;view=1up;seq=1 to the ends the URLs.
Here’s the list of volumes from 1846 to 1869 in the “Making Of America” site from Cornell.
Here’s a “Snippet” and “No Preview” list from Google Books. And here’s another “Snippet” and “No Preview” list also from Google Books.
There are lots of extras and duplicates of volumes from various other university libraries, but I have included only one copy of each volume. Where there are no copies at all in Hathi, I have substituted the copy from the “Making Of America” site from the Cornell University Library. Their copies go up to 1869 only, so a few later volumes after 1870 are still missing in Hathi.
Old Series
v.1 1845-46 http://babel.hathitrust.org/cgi/pt?id=uc1.31822028474377 (No preview)
v.2 1846-47 http://babel.hathitrust.org/cgi/pt?id=pst.000062998932;view=1up;seq=1
v.3 1847-48 http://babel.hathitrust.org/cgi/pt?id=uc1.31158007775348;view=1up;seq=1
v.4 1848-49 http://babel.hathitrust.org/cgi/pt?id=umn.31951001919664d;view=1up;seq=1
v.5 1849-50 http://babel.hathitrust.org/cgi/pt?id=umn.319510013896847;view=1up;seq=1
v.6 1850-51 http://babel.hathitrust.org/cgi/pt?id=uc1.31158007775322;view=1up;seq=1
v.7 1851-52 http://babel.hathitrust.org/cgi/pt?id=uc1.31158006604465;view=1up;seq=1
v.8 1852-53 http://babel.hathitrust.org/cgi/pt?id=uc1.l0051153724;view=1up;seq=1
v.9 1853-54 http://babel.hathitrust.org/cgi/pt?id=uc1.31158007775314;view=1up;seq=1
v.10 1854-55 http://ebooks.library.cornell.edu/s/scia/index.html
v.11 1855-56 http://babel.hathitrust.org/cgi/pt?id=pst.000062999014;view=1up;seq=1
v.12 1856-57 http://ebooks.library.cornell.edu/s/scia/index.html
v.13 1857-58 http://babel.hathitrust.org/cgi/pt?id=pst.000062999038;view=1up;seq=1
v.14 1859 http://ebooks.library.cornell.edu/s/scia/index.html
New Series
v.1 1859 http://ebooks.library.cornell.edu/s/scia/index.html
v.1 1859 https://books.google.ca/books?id=90hGAQAAIAAJ
v.2 1860 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538228;view=1up;seq=1
v.3 1860 http://babel.hathitrust.org/cgi/pt?id=pst.000062999076;view=1up;seq=1
v.4 1861 http://babel.hathitrust.org/cgi/pt?id=pst.000062999083;view=1up;seq=1
v.5 1861 http://babel.hathitrust.org/cgi/pt?id=pst.000062999090;view=1up;seq=1
v.6 1862 http://ebooks.library.cornell.edu/s/scia/index.html
v.7 1862 http://ebooks.library.cornell.edu/s/scia/index.html
v.8 1863 http://babel.hathitrust.org/cgi/pt?id=pst.000062999113;view=1up;seq=1
v.9 1863 http://babel.hathitrust.org/cgi/pt?id=pst.000062999120;view=1up;seq=1
v.10 1864 http://babel.hathitrust.org/cgi/pt?id=pst.000062999137;view=1up;seq=1
v.11 1864 http://ebooks.library.cornell.edu/s/scia/index.html
v.12 1865 http://ebooks.library.cornell.edu/s/scia/index.html
v.13 1865 http://babel.hathitrust.org/cgi/pt?id=pst.000062999151;view=1up;seq=1
v.14 1866 http://babel.hathitrust.org/cgi/pt?id=pst.000062999168;view=1up;seq=1
v.15 1866 http://babel.hathitrust.org/cgi/pt?id=uva.x001518006;view=1up;seq=1
v.16 1867 http://babel.hathitrust.org/cgi/pt?id=pst.000062999182;view=1up;seq=1
v.17 1867 http://babel.hathitrust.org/cgi/pt?id=umn.31951d00400811q;view=1up;seq=1
v.18 1868 http://babel.hathitrust.org/cgi/pt?id=umn.31951d00400812o;view=1up;seq=1
v.19 1868 http://babel.hathitrust.org/cgi/pt?id=umn.31951d00400813m;view=1up;seq=1
v.20 1869 http://babel.hathitrust.org/cgi/pt?id=umn.31951d00400814k;view=1up;seq=1
v.21 1869 http://babel.hathitrust.org/cgi/pt?id=umn.31951d00400815i;view=1up;seq=1
v.22 1870 http://babel.hathitrust.org/cgi/pt?id=umn.31951d00400816g;view=1up;seq=1
v.23 1870 http://babel.hathitrust.org/cgi/pt?id=pst.000062999250;view=1up;seq=1
v.24 1871 http://babel.hathitrust.org/cgi/pt?id=pst.000062999267;view=1up;seq=1
v.25 1871 http://babel.hathitrust.org/cgi/pt?id=pst.000062999274;view=1up;seq=1
v.26 1872 http://babel.hathitrust.org/cgi/pt?id=coo.31924096376227;view=1up;seq=1
v.27 1872 http://babel.hathitrust.org/cgi/pt?id=pst.000062999298;view=1up;seq=1
v.28 1873 http://babel.hathitrust.org/cgi/pt?id=pst.000062999304;view=1up;seq=1
v.29 1873 http://babel.hathitrust.org/cgi/pt?id=pst.000062999311;view=1up;seq=1
v.30 1874 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538350;view=1up;seq=1
v.31 1874 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538368;view=1up;seq=1
v.32 1875 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538376;view=1up;seq=1
v.33 1875 http://babel.hathitrust.org/cgi/pt?id=pst.000062999359;view=1up;seq=1
v.34 1876 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538392;view=1up;seq=1
v.35 1876 http://babel.hathitrust.org/cgi/pt?id=pst.000062999373;view=1up;seq=1
v.36 1877 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538400;view=1up;seq=1
v.37 1877 http://babel.hathitrust.org/cgi/pt?id=pst.000062999397;view=1up;seq=1
v.38-39 1878 http://babel.hathitrust.org/cgi/pt?id=pst.000062999403;view=1up;seq=1
v.39 1878 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538434;view=1up;seq=1
v.40 1879 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538442;view=1up;seq=1
v.41 1879 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538459;view=1up;seq=1
v.42 1880 http://babel.hathitrust.org/cgi/pt?id=pst.000062999434;view=1up;seq=1
v.43 1880 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538475;view=1up;seq=1
v.44-45 1881 http://babel.hathitrust.org/cgi/pt?id=pst.000062999458;view=1up;seq=1
v.45 1881 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538491;view=1up;seq=1
v.46 1882 http://babel.hathitrust.org/cgi/pt?id=pst.000062999465;view=1up;seq=1
v.47 1882 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538509;view=1up;seq=1
v.48 1883 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538517;view=1up;seq=1
v.49 1883 http://babel.hathitrust.org/cgi/pt?id=pst.000062999496;view=1up;seq=1
v.50-v.51 1884 missing
v.52 1885 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538566;view=1up;seq=1
v.53 1885 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538574;view=1up;seq=1
v.54 1886 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538525;view=1up;seq=1
v.55 1886 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538582;view=1up;seq=1
v.56 1887 http://babel.hathitrust.org/cgi/pt?id=pst.000062999557;view=1up;seq=1
v.57 1887 http://babel.hathitrust.org/cgi/pt?id=pst.000062999564;view=1up;seq=1
v.58 1888 http://babel.hathitrust.org/cgi/pt?id=pst.000062999571;view=1up;seq=1
v.59 1888 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024538624;view=1up;seq=1
v.60 1889 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024546692;view=1up;seq=1
v.61 1889 http://babel.hathitrust.org/cgi/pt?id=umn.319510013897568;view=1up;seq=1
v.62 1890 http://babel.hathitrust.org/cgi/pt?id=pst.000062999625;view=1up;seq=1
v.62-63 1890 http://babel.hathitrust.org/cgi/pt?id=chi.20130076;view=1up;seq=1
v.64 1891 http://babel.hathitrust.org/cgi/pt?id=umn.319510013897592;view=1up;seq=1
v.65 1891 missing
v.66 1892 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024546866;view=1up;seq=1
v.67 1892 http://babel.hathitrust.org/cgi/pt?id=pst.000062999687;view=1up;seq=1
v.68 1893 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024546841;view=1up;seq=1
v.69 1893 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024546833;view=1up;seq=1
v.70-71 1894 http://babel.hathitrust.org/cgi/pt?id=pst.000062999717;view=1up;seq=1
v.72 1895 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024546809;view=1up;seq=1
v.72-73 1895 http://babel.hathitrust.org/cgi/pt?id=chi.15625386;view=1up;seq=1
v.74 1896 http://babel.hathitrust.org/cgi/pt?id=pst.000062999748;view=1up;seq=1
v.75 1896 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024546775;view=1up;seq=1
v.76 1897 http://babel.hathitrust.org/cgi/pt?id=pst.000062999762;view=1up;seq=1
v.77 1897 http://babel.hathitrust.org/cgi/pt?id=pst.000062999779;view=1up;seq=1
v.78 1898 http://babel.hathitrust.org/cgi/pt?id=mdp.39015084561375;view=1up;seq=1
v.79 1898 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024546759;view=1up;seq=1
v.80 1899 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024546742;view=1up;seq=1
v.81 1899 http://babel.hathitrust.org/cgi/pt?id=mdp.39015024546734;view=1up;seq=1
v.82 1900 http://babel.hathitrust.org/cgi/pt?id=umn.319510013897762;view=1up;seq=1
v.83 1900 missing
v.84 1901 http://babel.hathitrust.org/cgi/pt?id=mdp.39015084561359;view=1up;seq=1
v.85 1901 http://babel.hathitrust.org/cgi/pt?id=pst.000062999854;view=1up;seq=1
v.86 1902 http://babel.hathitrust.org/cgi/pt?id=umn.31951d00400818c;view=1up;seq=1
v.87 1902 missing
v.88 1903 http://babel.hathitrust.org/cgi/pt?id=pst.000062999885;view=1up;seq=1
v.89 1903 http://babel.hathitrust.org/cgi/pt?id=pst.000062999892;view=1up;seq=1
v.90 1904 http://babel.hathitrust.org/cgi/pt?id=pst.000062999908;view=1up;seq=1
v.91 1904 http://babel.hathitrust.org/cgi/pt?id=pst.000062999915;view=1up;seq=1
v.92 1905 http://babel.hathitrust.org/cgi/pt?id=pst.000062999922;view=1up;seq=1
v.93 1905 http://babel.hathitrust.org/cgi/pt?id=pst.000062999939;view=1up;seq=1
v.94 1906 http://babel.hathitrust.org/cgi/pt?id=pst.000062999946;view=1up;seq=1
v.95 1906 http://babel.hathitrust.org/cgi/pt?id=pst.000062999953;view=1up;seq=1
v.96 1907 http://babel.hathitrust.org/cgi/pt?id=umn.31951d00400826d;view=1up;seq=1
v.97 1907 http://babel.hathitrust.org/cgi/pt?id=umn.31951d00400827b;view=1up;seq=1
v.98 1908 http://babel.hathitrust.org/cgi/pt?id=umn.31951d004008289;view=1up;seq=1
v.99 1908 http://babel.hathitrust.org/cgi/pt?id=pst.000062999991;view=1up;seq=1
v.100 1909 http://babel.hathitrust.org/cgi/pt?id=pst.000063000009;view=1up;seq=1
v.101 1909 http://babel.hathitrust.org/cgi/pt?id=pst.000063000016;view=1up;seq=1
v.102 1910 http://babel.hathitrust.org/cgi/pt?id=pst.000063000023;view=1up;seq=1
v.103 1910 http://babel.hathitrust.org/cgi/pt?id=pst.000063000030;view=1up;seq=1
v.104 1911 http://babel.hathitrust.org/cgi/pt?id=pst.000063000047;view=1up;seq=1
George Kovalenko.
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