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.

要使橡胶硬而结实的方法——也就是我们所说的“化”——就是要掺入磺加热，这一点现在已是常识了。

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.

使橡胶硬而结实的方法——也就是我们所说的“化”——就是掺入磺加热，这一点现在已经是。

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.

要使橡胶硬而结实的方法——也就是我们所说的“化”——就是要掺入磺加热，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.

要使橡胶硬而结实的方法——是我们所说的“化”——是要掺入热，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.

要使橡胶硬而结实的方法——也就是我们所说的“化”——就是要掺入磺加热，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.

要使橡胶实的方法——也就是我们所说的“化”——就是要掺入磺加热，这一已经是常识了。

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.

要使橡胶硬而结实的方法——也就是我们所说的“化”——就是要掺入磺加热，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.

要使橡胶硬而结实方法——也就是我们所说“化”——就是要掺入磺加热，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.

要使橡胶硬而结实的方法——也就是我们所说的“化”——就是要掺入磺加热，这一点现在已是常识了。