The years following Benjamin Coston's death were filled with more tragedy for Martha Coston; two of her children and her mother died in the next two years, leaving her in poor condition emotionally as well as in difficult financial straits. While searching through her husband's papers, she discovered the notes he had written on night signaling at the Navy Yard. Her husband's incomplete work needed substantial additional effort before it could be turned into a practical signaling system. For nearly ten years, Martha Coston worked to develop a system of flare signaling based on her husband's earlier work. With a limited knowledge of chemistry and
pyrotechnics, she relied on the advice of hired chemists and fireworks experts, with mixed results. A breakthrough came in 1858, while she was witnessing the fireworks display in
New York City celebrating the completion of the
transatlantic telegraph cable; she realized that her system needed a bright blue flare, along with the red and white she had already developed. she established the Coston Manufacturing Company to manufacture the signal flares, and entered into a business relationship with a pyrotechnics developer to provide the necessary blue color. On April 5, 1859, she was granted U.S. Patent number 23,536 for a pyrotechnic night signal and code system. (The patent was granted to her as administratrix for her deceased husband, who is named as inventor.) Using different combinations of colors, it enabled ships to signal to one another, and to signal to shore. Captain C.S. McCauley of the U.S. Navy recommended the use of her flares to Secretary of the Navy
Isaac Toucey in 1859. After extended testing, which demonstrated the effectiveness of the system, the U.S. Navy ordered an initial set of 300 flares, and later placed an order for $6000 worth of the flares. ==International successes and the Civil War==