Chapter I: Preface

The main purpose of the present work is to be a handy book of reference for draughtsmen engaged chiefly in Topographical Drawings. But to have limited its use to one class of draughtsmen, and especially to the skilled members of that class, would have necessitated the discovery of more cogent reasons for its publication than its author has yet been able to adduce. Works of such a character exist already, and though their imperfections are numerous, they fulfil their purpose in a fairly satisfactory manner. But had the field been clear in this direction, it is so restricted in extent that to have entered upon it would have been to undertake a labour that promised little fruit, for such a work could be only of small utility even to those for whom it was specially intended. It was, therefore, determined to make the present handbook _generally_ useful by giving it a much wider scope. And hence, if the intention has been efficiently carried out, it may claim a place in every drawing office, be it that of the Topographer, the Hydrographer, the Surveyor, the Military, Civil, or Mechanical Engineer, or the Architect. Whether or not this degree of success has been achieved, is not for the author to judge. But should he have failed to reach the high mark at which he has aimed, he hopes, with some degree of confidence, that he has at least succeeded in producing a book which the experienced draughtsman will find valuable as a book of reference, and which the pupil may constantly consult with profit. A want has long been felt by draughtsmen for some work of this kind to which they might refer their pupils in the office, and it may not be presumptive to suppose that the present work has supplied that want. To render it convenient for this twofold purpose, it has been divided into two parts. In the first part the principles and practices of the art have been clearly but briefly explained and illustrated; while in the second part, the application of the principles previously learned has been treated of, and such information given as relates directly to the duties of the practitioner.

Of course, in a work of the present character, originality in the matter is neither to be expected nor desired; enough if the manner shows some novelty, and is such as to add value to the matter.

Although the preparation of maps and plans has received the chief share of attention, engineering, architectural, and mechanical drawings have been largely treated of. Projection, orthographic, isometric and perspective, has been altogether omitted as beyond the scope of the work; but Colouring and Shading have been fully considered and profusely illustrated.

The Plates appended as examples for reference are numerous and varied in character; they have been specially prepared by B. Alexander, to whom the author offers his warmest thanks for the truly admirable manner in which he has executed the work entrusted to him.

16, CRAVEN STREET, CHARING CROSS,
_September 7th, 1874_.

CONTENTS.

PART I.--THE ESSENTIAL ELEMENTS.

SECTION I.--THE DRAWING OFFICE AND ITS FURNISHINGS.

PAGE

The Drawing Office 1
Instruments 2
Materials 5
Precautions and Remarks 9

SECTION II.--GEOMETRICAL PROBLEMS. 15

SECTION III.--LINES, DOTS, AND THEIR COMBINATIONS.

Straight and Curved Lines 27
Lines of uneven thickness 30
The Broken Line 30
The Dotted Line 31
Combinations of Straight, Broken, and Dotted Lines 31
The Wavy Line 33
Grass-land 34
Swamps and Marshy Ground 35
Sand and Gravel 35
Woodland 36
Uncultivated Land 37
Contour Lines 37

SECTION IV.--COLOURS.

Flat-tints 40
Conventional Colours 44
Water 45
Grass-land 45
Marsh 45
Sand and Gravel 46
Mud 46
Woodland 46
Cultivated Land 47
Uncultivated Land 47
Buildings 47
Roads and Streets 47
Fences 47

SECTION V.--SHADING.

Application of Shade Lines 48
Cylindrical Surfaces 50
Shading Lines 50
Shading Lines on Cylindrical Surfaces 51
Shading Lines in Topographical Drawings 52
The Vertical System of Shading 57
Shading in Colours 63
Hill Slopes 63
Cylindrical Surfaces in Mechanical Drawings 64

PART II.--APPLICATIONS.

SECTION I.--LETTERING, BORDERING, AND NORTH POINTS.

Lettering 66
Borders 69
North Points 69

SECTION II.--SCALES.

Scales of Distances 70
Scales of Construction 74

SECTION III.--PLOTTING.

Reference Lines and Points 78
Plotted Points 78
To Plot Reference Lines and Points 78
To Plot Traverse Reference Lines 84
To Plot Detail 89
To Plot Contours 90
To Plot Sounded Points in Submerged Districts 90
Errors and Error-sheets 91
To Plot Vertical Sections 92
To lay down Gradients 95
To Plot a Section from a Contour Map 96

SECTION IV.--CIVIL ENGINEERS’ AND SURVEYORS’ PLANS.

Standing Orders of Parliament 98
„ „ „ Documents required 99
„ „ „ Plans 100
„ „ „ Book of Reference 101
„ „ „ Sections 101
Working Sections 103

_Regulations of Local Government Board_:--
Boundary Maps 104
Maps for Division into Wards 104
Plans of Proposed Works 105
General Plan 105
Detailed Plan 106
Mining Plans 106
Estate and Town Plans 107

SECTION V.--MAP DRAWING.

Single Stroke Streams 109
Double Line Streams and Rivers 110
Colouring Streams or Rivers 110
Islands and Sand-banks, Sandy and Pebbly Beds of Rivers 110
Roads and Pathways 111
Mountain Passes 111
Fords and Ferries, Toll-gates 111
Telegraph Lines and Stations 112
Railways, Stations, and Termini 112
Size of Cities, Towns, and Villages 112
Sketching, Shading, and Copying Hills 113
Field Sketching 114
Examination of Maps in the Field 118

SECTION VI.--MECHANICAL AND ARCHITECTURAL DRAWINGS. 121