Viewing page 57 of 70
It looks like you're using a mobile device. We recommend using a physical keyboard for transcription entry.
Alloys containing a large percentage of cadmium, zinc, or other low fusing metals are not suitable for enameling as the firing temperature, 1400 F., causes these metals to form oxides o the surface of the stock, before the enamel vitrified, producing holes or chipping. Holes are also caused by foreign matter on the surface of the article, or in the enamel. This burns, forming a bubble, which has its surface broken by stoning, leaving a hole Thos. H O'Brien
Please note that the language and terminology used in this collection reflects the context and culture of the time of its creation, and may include culturally sensitive information. As an historical document, its contents may be at odds with contemporary views and terminology. The information within this collection does not reflect the views of the Smithsonian Institution, but is available in its original form to facilitate research. For questions or comments regarding sensitive content, access, and use related to this collection, please contact email@example.com.