Publisher's Synopsis
Excerpt from the Foreward: "The following pages are more in the nature of a manuscript, or heart-to-heart talk between those who have mutual confidence in each other, than of a technical, or strictly scientific treatise of the subject in hand; and I cannot do better, for all parties concerned, than to explain, just here in the beginning, how this came about, and why I have concluded to leave the copy practically as it was originally written."