In the pages of this book, the author has sought to impart to
the beginner, such elementary information as would enable him,
with application and practice, to make simple mechanical
drawings without the assistance of a teacher.
To accomplish this end, it has been necessary to mainly confine
the subject-matter to the actual drawing of elementary pieces of
machinery, and in many cases to show the pencil lines of the
drawing, which possesses great advantages for the learner, since
it is the producing of the pencil lines that really proves the
study, the inking-in being merely a curtailed repetition of the
when the drawing of a piece, such, for example, as a fully
developed screw thread, is shown fully developed from end to
end, even though the pencil lines are all shown, yet the process
of construction will be less clear than if the process of
development be shown gradually along the drawing.
at an end of the example, the first pencil lines only may be
shown, and as the pencilling progresses to the right-hand, the
development may progress so that at the other, or left-hand end,
the finished inked-in and shaded thread may be shown, and
between these two ends will be found a part showing each stage
of development of the thread, all the lines being numbered in
the order in which they were marked. This prevents a confusion
of lines, and makes it more easy to follow or to copy the
The numerous inquiries from working machinists for a book of
this kind have led the author to its production, which he hopes
and believes will meet the want thus indicated, giving to the
learner a sufficiently practical knowledge of mechanical drawing
to enable him to proceed further by copying such drawings as he
may be able to obtain, or by the aid of some of the more
expensive and elaborate books already published on the subject.
He believes that in learning mechanical drawing without the aid
of an instructor the chief difficulty is overcome when the
learner has become sufficiently familiar with the instruments to
be enabled to use them without hesitation or difficulty, and it
is to attain this end that the chapter on plotting mechanical
motions and the succeeding examples have been introduced; these
forming studies that are easily followed by the beginner, while
sufficiently interesting to afford to the student pleasure as
well as profit.
July 15, 1889.