There are two main types of the field-book: 1. Single Line Field-Book 2. Double line Field-Book.
The field measurements, sketches and relevant notes are recorded for future reference in a note book, known as field-book. The field-book in general use is about 20cm * 12cm and opens length wise.
Type # 1. Single Line Field-Book (Fig. 3.18, b):
Every page of this kind of the field-book has a single red line ruled down the middle. This line represents the chain line and against it are entered the total length of the line and the changes at which the offsets are taken. The space on either side of the line is available for sketching the various features along the chain line and for writing the offset distances.
ADVERTISEMENTS:
The offsets are noted opposite to the changes from which they are taken to the right or left of the middle line according as they are on the right or left of the chain line.
Type # 2. Double Line Field-Book:
It is similar to the single line field-book but instead of a single red line in the centre, two blue or red lines about 1.5 cm apart are ruled down in the middle of each page. The space between these lines represents the chain line and is reserved for entering changes, which are thus kept entirely separate from the other dimensions.
Single line field-book is convenient for large scale and much detailed dimension-work while for ordinary work, the double line field-book is commonly used. The pages of the field-book are machine numbered.
