China’s first nuclear submarine was developed with the aid of an abacus, according to the scientist who led the project in the late 1950s.

Now 93, Huang Xuhua, chief designer of the Long March-1, said he still owns one of the suanpan [abacuses] that were used by his team almost 60 years ago, Chutian Metropolis Daily reported on Monday.

“Lots of critical data used in the development of the nuclear submarine jumped out from this suanpan,” he was quoted as saying.

Often referred to as the “Father of China’s nuclear subs” Huang worked for China Shipbuilding Industry Corporation, which had several abacus calculation teams divided into specialist sections, he said.

Scientists “attacked the beads [on their abacuses] until every section reached the same result,” he said, adding that the constant clattering was enough to make entire buildings “rattle from dawn until dusk.”

Read the whole story from The South China Morning Post.

Featured image courtesy of Wikimedia Commons