Opinion ID: 1563058
Heading Depth: 1
Heading Rank: 2

Heading: The use of hard rubber:

Text: We agree with the master and the trial judge in the conclusion that the prior art above referred to disclosed the use of hard rubber in a water lubricated bearing and that unless invention would result from substituting soft rubber for hard rubber the patents in question were anticipated by the prior art. The term hard rubber is applied to a product resulting from vulcanizing an equal mixture of sulphur and rubber with occasional addition of other material. See patent No. 8,075 issued May 6, 1851 to Nelson Goodyear. As the result of this process the rubber loses its principal characteristics of elasticity and resilience and the product, although retaining some degree of elasticity, approaches the rigidity of metal. It might be quite as well called hard sulphur for it is a distinct and definite product with characteristics quite distinct from that of rubber.