"Heinke Brothers", 78-78 Great Portland Street, London, "Submarine Engineers"; that firm lasted until 1867. 1869: Charles Edwin Heinke died after being in ill-health for 2–3 years 1870: John William Heinke died from congestion of the liver after an 11-month illness. These two deaths disorganized company business. 1871: Frederick William Heinke and one William Griffin Davis AICE formed a new firm 'Heinke & Davis' at 176 Great Portland Street, London. It moved to 2 Brabant Court, Philpot Lane, London. It was bankrupt by January 1879. 1871: Gotthilf Frederick Heinke died 1871: Gotthilf Henry Heinke became a sleeping partner in the business and took on a partner William Foster to manage the business; they started a new business 'C.E.Heinke & Co, Submarine Engineers'. 1880: Frederick William Heinke was forced to seek work in North America, but died of a fever in 1883 in Tecomabaca, Oaxaca, Mexico. 1884: Gotthilf Henry Heinke retired for ill health, and sold his company to William Foster and Robert Fox (his brother in law) who had also become involved in the business, but continued to live on the upper floor of 79 Great Portland Street till his death in 1899 20th century 1902: Robert Fox died. 'Foster and Williams' was merged into 'C.E.Heinke & Co, Submarine Engineers'. 1904: The lease on Great Portland Street expired. Production was moved to Foster and Williams's premises. 1905: The company got 10,000 more square feet of work area. 1905: All Heinke helmets made until 1905 had the butterfly style wingnuts; after that regular wingnuts were used. 1922: C.E.Heinke & Co, Submarine Engineers became a limited company 'C.E.Heinke & Co Ltd, Submarine Engineers', making a good living from standard diving equipment. WWII and after WWII blitz: Many company records were lost. 1950: After this date the firm's fortunes declined, as with Siebe Gorman. Mid to late 1950s: the firm starts making "Heinke-Lung" aqualungs, Delta dry suits, Dolphin and Falla wetsuits, Hans Hass diving masks, swimming fins and snorkel tubes. 1958: Heinke donated the Heinke Trophy to the British Sub-Aqua Club (BSAC). This trophy is awarded annually to the BSAC branch judged to have done the most to further the interests of its own members and of the BSAC. 1961: The firm was incorporated into Siebe Gorman. The last Heinke diving helmet went out of production in 1961. A few helmets were given the tag of "Siebe-Heinke", but eventually the name Heinke completely disappeared.