Late Ming Dynasty

Echizento any idea why the difference in pronunciation http://www.sportstune.com/chinese/c...ungchen.html

Ch'ung Chen T'ung Pao

There are several different ways of "Westernizing" Chinese script. The older "Wade-Giles" method is the commonest of the old colonial-era forms and is still preferred in Hong Kong and Taiwan. Mainland China and Singapore prefer to use the "Pinyin" system, which was invented by the Communist Chinese.

The easy way to tell the difference at-a-glance: Wade-Giles makes extensive use of apostrophes: Ch'ien, T'ung, and so forth. Pinyin, on the other hand, uses the letters "X" and "Q" a lot - as in Xi, Qian, etc.

Which you end up using depends largely, as echizento said, on what the books or websites you refer to are using. Krause and most older works such as Schojth use Wade-Giles, while Hartill and Jen (Cash Coin catalogues) use Pinyin.