Talking about the media for the first bout of large scale transmission of European science and technology to China before the Opium War in 1840, it is very easy for us to overlook the role played by objects other than books, objects such as clocks, musical organs, medicine, and scientific instruments. These objects are no less bearers of knowledge than books, not just in terms of the technical know-how for their making and using, but also concerning the underlying principles and theories tacitly embedded in their structures and functions, just as a slide rule embodies the rules of logarithm, while an orrery represents a geocentric or heliocentric cosmology. In this paper, I will present a special category of objects, i.e. a line of optical toys, or “instruments for recreation” and “philosophical toys” as were called by people in modern Europe. They were deployed by Jesuit missionaries in various occasions from the palace to churches mostly as exotic wonders to show the superiority of European science and arts and thus to prove the soundness and credibility of European religion. In the eyes of ordinary Chinese literati and public, these objects were exotic and wonderful enough to become subjects of literary writings as well as playthings for festival ceremonies and entertainments. In the hands of Chinese artisans and mathematicians, however, the “object-borne knowledge” in these “western wonders” was more attractive and intriguing. Not only did the knowledge be abstracted, copied and adapted to the local context of commodity production and consumption, but it was also mixed with the “text-borne knowledge” and began an interesting process of knowledge fermentation which led directly to the birth of a special system of optics totally different from what had been established by modern opticists in Europe. This paper will trace how the role of the same category of objects changed in different socio-cultural contexts.