88 NOTES ON THE OBSERVATION OF BIRDS. 
on the sand bars, along the lake shores, on the banks of 
rivers, and in the marshes. 
The observer must visit all localities—marshes, swamps, 
hardwood and pine forests, fields, meadows, low creek 
bottoms, and in fact all places presenting any diversity of 
conditions, if he wishes to know every bird of his locality. 
In the perusal of nature, as in the reading of books, to 
derive the most benefit copious and accurate notes must be 
taken. The memory is a treacherous servant and cannot be 
depended on; therefore we must take our notes in the field 
and then rewrite them at leisure in the study. 
During migrations the number and sex, if possible, of each 
species seen on the first days of its appearance should be 
taken. Such observations become invaluable when compar- 
ing notes with other observers, to determine the time elaps- 
ing in the passage of the birds from station to station, and 
the route taken. Such a record, covering the observations of 
several years, will be interesting as showing the regularity 
with which the different species come and go. Thoreau is 
said to have been so careful an observer that should he have 
fallen into a deep sleep lasting many years, on awaking, he 
could have told the day of the month by the flowers that 
were blooming and the birds warbling about him. Such a 
high degree of excellence cannot be achieved without the 
greatest care in the regularity with which our observations 
are made and in the preparation of notes, guided always by 
our love for the study. 
During migrations we should also note the exact locality 
where first appearance was made, conditions of weather, 
temperature, etc. At all times the kinds and quantities of 
food taken, that we may determine the utility of the different 
species and protect them from their numerous enemies. 
Carefully noting everything of importance, all songs and 
call notes, nesting habits, peculiar movements on foot and 
wing, and preferences for certain localities, soon we will be- 
come so thoroughly acquainted with our feathered friends, 
