By what year had the British Royal Navy extensively adopted stockless anchors after several years of trials?

Answer

1903

Although the stockless principle was patented earlier, the adoption by the British mercantile marine gained momentum in the late 19th century, culminating in the Royal Navy adopting them in 1903 after trials initiated in 1885.

By what year had the British Royal Navy extensively adopted stockless anchors after several years of trials?
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