Transcriber's Notes: There were a number of printer's errors in punctuation that have been corrected silently.

The following changes in spelling have been made:

Page 26 breedidg is now breeding
Page 31 aovided is now avoided
Page 32 ean is now can
Page 32 commonn is now common
Page 38 crossiug is now crossing
Page 54 advantange is now advantage
Page 67 disadvantange is now disadvantage
Page 81 disadvantange is now disadvantage
Page 85 controled is now controlled
Page 86 aide is now aside

The coverpage is placed in the public domain.