Model of the Mathematical Bridge Designed by Rong Youying

The Model of the Mathematical Bridge Designed by Rong Youying was a 1:250 representation of Newton’s Mathematical Bridge, based on Rong Youying’s design and built using 388 nails. Presented at N University by Sir Joseph Larmor in 1913, it carried her mathematical achievement into the university’s public identity; its destruction in the bombing of 1943 later made the model a material casualty of the institution’s destruction as well.

Design and Presentation

In the summer of 1913, Sir Joseph Larmor, president of the Newtonian Mathematical Society, visited China with the model. Rong Youying had designed a version of the Mathematical Bridge using only 388 nails. The account says that the model was constructed in the grounds of N University, where Larmor’s gift made the university still more prominent.

The model linked an individual design to a larger institutional history. By the time it arrived, Rong Youying’s former Lillie’s Academy of Mathematics had become N University, and she had returned from Cambridge University to lead its mathematics department. The miniature bridge thus represented both her ingenuity and the mathematical reputation that the university sought to cultivate.

Loss and Aftermath

Japanese bombing burned N University to the ground in October 1943, destroying the model. The account identifies it as a remarkable gift from Larmor and specifies its scale, 1:250, making the loss concrete: the surviving representation of Rong Youying’s bridge design perished with the university buildings.

Rong Youying had died in childbirth in 1914, the year after Larmor’s visit and before she was forty. The model therefore outlasted its designer by nearly three decades, but not the institution that had displayed it. Its destruction closes the object’s documented history with a sharp contrast: the bridge design had helped raise the university’s profile, while the bombing erased both the university and this physical record of her work.