Principles and practice of crown and bridgework : a practical, systematic and modern treatise upon the requirements and technique of artificial crown and bridgework / By Hart J. Goslee.

  • Goslee, Hart J., 1871-1930.
Date:
1913
Catalogue details

Licence: Public Domain Mark

Credit: Principles and practice of crown and bridgework : a practical, systematic and modern treatise upon the requirements and technique of artificial crown and bridgework / By Hart J. Goslee. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

    30/634 (page 20)
    Silver solder is an alloy of copper, silver and Silver Solder. zinc, with silver in the greatest proportion, and is much used in the making of gold solders, as the alloy, as well as being an economical hard solder for various lines of work where brass and German silver are used. A common formula is: Silver, 6 parts. Copper, 3 Zinc, I part. German silver is used to some extent in tempo- Gcrman Silver. rary work of all kinds, such as dowels for temporary crowns and bands for matrices, etc. It is com- posed of copper and zinc, with the addition of nickel, which increases the fusing point and gives a harder, tougher alloy. The following formula is much used: Copper, 50 parts. Zinc, 30 Nickel, 20 Fusible alloys are those in which the lower fus- Tuslble Jllloys. ing metals are combined, such as lead, tin, bismuth, antimony, and cadmium, and are intended for use in making dies and counterdies for swaging in crown-work, and for the purpose of obtaining models direct from plaster impressions, or from the mouldine compounds suggested by Dr. George W. Mellotte, and composed of potter's clay and glycerine. The extreme fusibility of these alloys depends to a great extent upon the proportion of bismuth incorporated, and varies accordingly. The following are formulae of the various known alloys of this nature: Newton's Alloy. Bismuth, 8 Lead, 5 Tin, 3 Fusing point, 200° F. F. Hodgen's Alloy. Bismuth, 8 Lead, 5 Tin, 3 F. Antimony, 2 Fusing point, 224° F. Wood's Alloy. Bismuth, 5 Lead, 4 Tin, 2 Cadmium, I Fusing point. 140 Rose's Alloy. Bismuth, 8 Lead, 8 Tin, 3 Fusing point. 174'