It is common knowledge now that the way to make rubber hard and strong -- to "vulcanize" it, as we say -- is by heating it with sulphur.

要使橡实的方法——也就是我们所说的“硫化”——就是要掺入硫磺加热，这一点现在已经是常识了。

It is common knowledge now that the way to make rubber hard and strong -- to "vulcanize" it, as we say -- is by heating it with sulphur.

要使橡硬而结实的方法——也就我们所说的“硫化”——就要掺入硫磺加热，这一点现在已识了。

It is common knowledge now that the way to make rubber hard and strong -- to "vulcanize" it, as we say -- is by heating it with sulphur.

要使橡硬而结实的方法——也就是我们所说的“硫化”——就是要掺入硫磺加热，这一点经是常识了。

It is common knowledge now that the way to make rubber hard and strong -- to "vulcanize" it, as we say -- is by heating it with sulphur.

使硬而结实的方法——也我们所说的“硫化”——掺入硫磺加，这一点现在已经常识了。

It is common knowledge now that the way to make rubber hard and strong -- to "vulcanize" it, as we say -- is by heating it with sulphur.

要使橡硬而结实的方法——也就是我们所说的“硫化”——就是要掺入硫磺加，点现在已经是常识了。

It is common knowledge now that the way to make rubber hard and strong -- to "vulcanize" it, as we say -- is by heating it with sulphur.

要使橡硬而结实的方法——也就是我们所说的“硫化”——就是要掺入硫磺加热，这一点现在已经是常识了。

It is common knowledge now that the way to make rubber hard and strong -- to "vulcanize" it, as we say -- is by heating it with sulphur.

要使橡硬而结实方法——也就是我们所说“硫化”——就是要掺入硫磺加热，这一点现在已经是常识了。

It is common knowledge now that the way to make rubber hard and strong -- to "vulcanize" it, as we say -- is by heating it with sulphur.

要使橡硬而结实的方法——我们所说的“硫化”——要掺入硫磺加热，这一点现在已经常识了。

It is common knowledge now that the way to make rubber hard and strong -- to "vulcanize" it, as we say -- is by heating it with sulphur.

要使橡硬而结实的方法——也就是我们所说的“化”——就是要掺入热，这一点现在已经是常识了。