TRANSCRIBERS' NOTES

The following discrepancies in the text are as in the original:

toxine, insiduous, efficaceous, cyanid are spelt as in the original

In the first paragraph of chapter XII, "the student might not be lead" is as in the original. Lead perhaps should be led

There is no Figure 147 in the original

In the bibliography, the entry for Vaughan without a text specified is as in the original