- Martin, H. Newell (Henry Newell), 1848-18961
- McKenzie1
- McPherson, Samuel Dace1
- Meadows, Alfred, 1823-18871
- Medical instruments1
- Medicine -- Periodicals1
- Microscope1
- Microscopes1
- Miller, James, 1812-18641
- Milne-Edwards, Henri, 1800-18851
- Morgan, Campbell de, 1811-18761
- Murchison, Charles, 1830-18791
- Murchison, Roderick Impey, Sir, 1792-18711
- Nelaton, Auguste, 1807-18731
- Niemeyer1
- Nunnely, Thomas, 1809-18701
- Oppolzer, Johann, Ritter von, 1808-18711
- Paget, George Edward, Sir, 1809-18921
- Pajot, Charles, 1816-18961
- Partridge, Richard, 1805-18731