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MERCHANT
VESSELS



BY

ROBERT RIEGEL, Ph.D.

PROFESSOR OF INSURANCE AND STATISTICS
IN THE UNIVERSITY OF PENNSYLVANIA




D. APPLETON AND COMPANY

NEW YORK LONDON

1921



'



COPYRIGHT, 1921, BY

D. APPLETON AND COMPANY



PRINTED IN THE UNITED STATES OT AMERICA



EDITORS' PREFACE

THIS is the fourth volume of a series dealing with the business
of ocean shipping and transportation. The first volume, Ocean
Steamship Traffic Management, by Professor G. G. Huebner, bore
the following Editors' Preface :

"This volume upon the management of ocean steamship traffic
is the first of a series of manuals designed to assist young men
in training for the shipping business. The necessity for such
a series of manuals became evident when, as a result of the great
war, the tonnage of vessels under the American Flag was, within
a brief period, increased many fold. To carry on the war, and
to meet the demands of ocean commerce after the war, the United
States Government, through the Shipping Board and private ship-
yards, brought into existence a large mercantile marine. If these
ships are to continue in profitable operation under the American
Flag, the people of the United States must be trained to operate
them. Steamship companies, ship-brokers and freight forwarders
must all be able to secure men necessary to carry on the commer-
cial and shipping activities that make use of the ships. A suc-
cessful merchant marine requires ships, men to man the ships,
and business organization to give employment to the vessels.

"In its Bulletin upon 'Vocational Education for Foreign Trade
and Shipping' (since republished as 'Training for Foreign Trade/
Miscellaneous Series No. 97, Bureau of Foreign and Domestic
Commerce, for sale by the Superintendent of Documents), the
Federal Board for Vocational Education includes among other
courses suggested for foreign trade training two shipping courses
upon subjects with which exporters should be familiar, namely,
'Principles of Ocean Transportation' and 'Ports and Terminals/
Although such general courses are helpful to the person engaging
in the exporting business, a training for the steamship business
as a profession requires much greater detail in the knowledge of

v

52574



vi EDITORS' PREFACE

concrete facts of a routine nature. An analysis was made of the
various divisions of the steamship office organization and it was
suggested to the United States Shipping Board that as no litera-
ture existed of sufficient practicability and detail, several manuals
covering the principal features of shore operations should be
written.

"The response of the Shipping Board was hearty. The Ship-
ping Board appointed Mr. Emory R. Johnson of its staff, then
conducting an investigation of ocean rates and terminal charges,
as editor. The Federal Board for Vocational Education desig-
nated Mr. R. S. MacElwee, then engaged in the preparation of
studies in foreign commerce. Before the project was completed
Mr. Johnson severed his connection with the Shipping Board, in
1919, and in January, 1919, Mr. MacElwee became Assistant
Director of the Bureau of Foreign and Domestic Commerce,
Department of Commerce. The interest of the editors in the
project did not terminate, however, and their close cooperation
has been voluntarily continued out of conviction that the works
will be helpful.

"The books have been written with a view to their being read
by individual students conducting their studies without guidance,
also with the expectation that they will be used as class text-
books. Doubtless colleges, technical institutes, and high schools
having courses in foreign trade, shipping business and ocean
transportation will desire to use these volumes as class texts in a
manner outlined in 'Training for the Steamship Business,' by R.
S. MacElwee, Miscellaneous Series 98, Bureau of Foreign and
Domestic Commerce, Superintendent of Documents, Washington,
D. C. It is expected that evening classes and part-time schools
organized under the patronage of the Federal Board for Voca-
tional Education, Chambers of Commerce, and other interested
organizations will find the manuals useful. Should these volumes
accomplish the desired purpose of giving the American people a
somewhat greater proficiency in the business of operating ships,
they will have proven successful."

This volume upon Merchant Vessels contains a non-techni-
cal, amply illustrated description of the main types of vessels and
their uses in different services. The discussion of the many prob-
lems connected with the measurement of vessels, their registra-



EDITOR'S PREFACE vii

tion, and tlieir tonnage is especially clear and valuable. The book
should be of interest to all students of ocean transportation, to
shippers, to vessel-owners, and to those engaged in the operation
of vessels.

THE EDITORS



AUTHOR'S PREFACE

THIS is one of a "Shipping Series" designed as a basis for in-
struction in the various phases of the steamship business, a se-
ries inspired and outlined by the editors, Dr. Emory R. Johnson
and Dr. R. S. MacElwee. As a part of such a series it assumes
the form of a specialized text, supplementing and being sup-
plemented by the other volumes of the series; but an effort has
been made to describe a definite phase of the steamship business
and in this particular field to produce a volume complete in
itself. It deals with the vessels of various types and equip-
ment employed in maritime commerce, their measurement and
classification.

Part I describes the competition between sail and steam; the
uses of the sailing vessel ; wood, steel and concrete ships and
their more essential parts; the various types of vessels employed
and their uses; and the principal kinds of marine engines. In
this Part the types of vessels and their purposes have been
given exceptional space. The treatment is intended to be eco-
nomic in character and no pretense is made of writing a tech-
nical treatise; on the contrary the sections dealing with con-
struction features and marine engines have been made as clear
and brief as possible and the advantages and disadvantages of
the various features emphasized. The diagrams are intended
to give accurate general impressions rather than mechanical
details and photographs have been employed in some cases.
Much of the information contained has hitherto existed only
in such scattered form as to be inaccessible to the average stu-
dent of transportation.

Part II deals with a phase of shipping activity upon which
the available literature is noticeably scant. Aside from brief
general remarks, government documents and foreign works, com-
paratively little information has been available on the pur-
poses of vessel measurement, the units and methods employed,
vessel measurement rules and the work of classification socie-

ix



x AUTHOR'S PREFACE

ties, in spite of the political, legal and economic significance of
these subjects. American rules, practices and institutions have
been emphasized, since foreign examples have often been pre-
sented elsewhere.

In preparing the list of references which appears at the end
of nearly every chapter the endeavor has been to include those
which are accessible and which contain a reasonable amount
of additional material on the subject in a form suitable for the
average reader, avoiding the usual complete but cumbersome
"bibliography," which fortunately is elsewhere available. Un-
fortunately but inevitably this often excluded excellent and val-
uable books, sometimes those from which the author derived
considerable assistance but whose technical character or inac-
cessibility made them unavailable for the purpose.

It is a pleasure to acknowledge the benefit derived from the
advice and assistance of Dr. Emory R. Johnson and the in-
formation furnished by the Bureau of Navigation, the Col-
lector of Customs at Philadelphia, officials of the Shipping
Board, Mr. G. P. Taylor of the American Bureau of Shipping
and vessel owners.

ROBERT RIEGEL



CONTENTS

PART I

CONSTRUCTION, TYPES AND USES OF MERCHANT
VESSELS

CHAPTER PAGE

I. METHODS OF PROPULSION 3

Types of sailing vessels The square and fore-and-aft
rig Combinations of these rigs The schooner the im-
portant modern sailing vessel Decline in importance of
the sailing vessel Causes of this decline The favor-
able features of sailing vessels Their uses at the pres-
ent time Summary References.

II. MATERIALS OF CONSTRUCTION 18

Essential construction features of a wooden vessel
Disadvantages of wood as a material for shipbuilding
Introduction of iron vessels Advantages of steel over
iron The composite vessel Concrete vessels Their
advantages and defects Statistics of wood, iron and
steel construction References.

III. STRUCTURAL FEATURES OF STEEL VESSELS 32

Longitudinal and transverse members Principal trans-
verse parts and their uses Longitudinal parts and their
uses The Isherwood system of construction Double
bottom tanks Forms, spaces and superstructures Ref-
erences.

IV. TYPES OF MERCHANT VESSELS 48

A classification of vessels Classification of merchant
vessels according to hull material Classification ac-
cording to form of hull Classification according to
speed and character of service Comparison of line and
tramp vessels as regards standardization, types of cargo,
contracts, methods of operation, types of vessels em-
ployed, relative economy, rates, earnings and extent of
r- tonnage.

V. TYPES OF MERCHANT VESSELS (Continued) 66

Classification according to strength of construction and
deck arrangements Relation of the load line to type
xi



xii CONTENTS

CHAPTER PAGE

Full-scantling vessel Three-deck vessel Two-deck
vessel One-deck vessel Raised-quarterdeck vessel
Shelter-deck vessel Well-deck vessel Flush-deck ves-
sel with superstructures Shade-deck vessel Whale-
back steamer Turret-deck vessel Trunk-deck vessel
Self-trimming vessel Cantilever vessel Corrugated
vessel Tank vessel Refrigerator vessel Steam
schooner Awning-deck vessel Spar-deck vessel Un-
rigged craft Modern developments in cargo vessels
References.

VI. TYPES OF MARINE ENGINES 103

Classification of steam engines The beam engine
Side-lever engine Oscillating engine Compound en-
gine Trunk engine Modern reciprocating engines
Turbine engines Types of turbine engines Advan-
tages and disadvantages of the turbine Marine boilers
References.

VII. OIL-BURNING AND INTERNAL-COMBUSTION ENGINES . .119
Oil-burning engines Their advantages and disadvan-
tages as compared with coal-burning engines Internal-
combustion gas engines Method of operation Advan-
tages and disadvantages of the producer-gas engine
Internal-combustion oil engines Operation of the
Diesel engine Advantages of the Diesel engine Ref-
erences.

PART II
THE MEASUREMENT OF MERCHANT VESSELS

VIII. KINDS OF TONNAGE AND THEIR USES 137

Various meanings of the word ton Relations between
different forms of tonnage Uses of vessel tonnage
Uses of displacement and dead-weight tonnage Use for
statistical purposes Legal use Taxation Charges for
services rendered Description of vessels Uses of
gross and net tonnage Statistical purposes Legal
purposes As a basis for taxation As a basis for serv-
ices rendered Description of vessels.

IX. DISPLACEMENT AND DEAD- WEIGHT TONNAGE . . . .157
Displacement tonnage Displacement and buoyancy
Forms of displacement Calculation of displacement
Displacement curve Immersion curve Dead-weight
tonnage Measurement of dead-weight Dead-weight
scale Relation between displacement and dead-weight
Rules for freeboard Load line legislation Princi-



CONTENTS xiii

CHAPTER PAGE

pies of load line legislation United States' legisla-
tion References.

X. GROSS TONNAGE 176

Definition of gross tonnage Steps in the process of
measurement Measurement process under United
States rules Tonnage under the tonnage deck 'Tween-
decks tonnage Superstructures and closed-in spaces
Spaces exempt because unenclosed Spaces exempt be-
cause of their purpose Principles governing gross ton-
nage measurement.

XI. NET TONNAGE 192

Nature of net tonnage Measurement of propelling-
power space Deductions for propelling space Deduc-
tions for crew space Deductions for navigating space
Principles of net tjonnage Example of calculation of
United States tonnage References.

XII. COMPARISON OF MEASUREMENT RULES 203

Important present-day measurement rules Summary of
the measurement process Comparison of United States,
British, German, Suez Canal and Panama Canal rules
Tonnage under the tonnage deck Between-deck ton-
nage Superstructures Spaces exempt below the ton-
nage deck Spaces exempt above the tonnage deck
Measurement of propeller-power space Necessity for
arbitrary rule The percentage method The Danube
rule The German rule Discussion of deductions for
propelling power Deductions for crew space Deduc-
tions for navigating space International tonnage
References.

XIII. THE MEASUREMENT OF SAFETY 229

Purposes of vessel classification Development of
classification societies Process of registration De-
scription of Lloyds' Register Other important registers
American Bureau of Shipping Description of the
American Register Lloyd's rules and tables for classi-
fication American Bureau of Shipping rules for con-
struction References.



LIST OF ILLUSTRATIONS

FIGURE PAGE

Frontispiece Whaleback steamer

1. Full-rigged ship 4

2. Schooner . . 5

3. Net tonnage of world's merchant^ marine 6

4. Sail and steam tonnage of the United States ..... 7

5. Sailing vessel routes of the world 10

6. Principal parts of a wooden vessel 20

7. Vessel stresses in still water . . . . 22

8. Vessel stresses in waves 23

9. Transverse stress 24

10. World's merchant marine wood, iron and steel .... 30

11. Keels 33

12. Transverse frames 34

13. Frame and shell plating . 35

14. Frames and floor plate 35

15. Keelson and stringers * 36

16. Beams and carlings 37

17. Floor plates and double bottom 38

18. Longitudinal system of framing exterior ..... 39

19. Transverse system of framing 40

20. Longitudinal system of framing interior 41

21. Profile, half-breadth and body plan 43

22. Spaces in a cargo vessel 45

23. Vessel with superstructures 45

24. Block coefficients 54

25. Three-deck vessel 70

26. Two-deck vessel 71

27. Raised-quarterdeck vessel 73

28. Raised-quarterdeck with extended bridge 74

29. Short raised-quarterdeck 75

30. Shelter-deck vessel 76

31. Shelter-deck vessel profile 77

32. Well-deck vessel 78

33. Vessel with superstructures 79

34. Shade-deck vessel 80

35. Whaleback steamer . 81

36. Turret-deck vessel 82

37. Turret-deck vessel 83

38. Trunk-deck vessel 84

xv



xvi LIST OF ILLUSTRATIONS



39. Trunk-deck vessel 85

40. Self-trimming vessel 86

41. Cantilever vessel 87

42. Cantilever vessel 88

43. Corrugated vessel 89

44. Tank vessel 91

45. Tank vessel 92

46. Steam schooner 95

47. Awning-deck vessel 97

48. Side-lever engine 105

49. Oscillating engine 106

50. Oscillating geared engine 107

51. Trunk engine . 108

52. Parsons turbine 112

53. Yarrow boiler 117

54. Semi-Diesel engine 133

55. Displacement scale 161

56. Immersion curve 162

57. Dead-weight scale 164

58. Freeboard marks 172

59. Tonnage length 181

60. Division of tonnage length and depths 181

61. Measurements of transverse section 182

62. Transverse sections 183

63. Measurement of 'tween-deck spaces . . . . . . . .187

64. Propelling power deductions 195

65. Tonnage calculation sheet Insert opposite 199

66. Tonnage certificate 199

67. Propelling power deductions compared 223

68. Lloyds' Register specimen page 235

69. American Register specimen page of "The Record" . . 239



PART I

CONSTRUCTION, TYPES AND USES OF
MERCHANT VESSELS



CHAPTER I
METHODS OF PROPULSION

In a study of the carriers of maritime commerce the distinction
between the sailing vessel and the steamer is a primary concept.
As to present-day functions of these craft, the circumstances
which led to the decline of the sailing vessel, and the qualities
which made steam preeminent as motive power, popular opinion
includes many misconceptions. Steam vessels were not immedi-
ately an overwhelming success, did not, in fact, displace the- sail-
ing vessel as fast as the automobile has displaced the horse, and,
to carry the analogy further, are still inferior to the sailing vessel
under some circumstances, as the motor vehicle is to the horse for
a limited kind of service. It is impossible here to revise these
conceptions by a history of the development of vessels but this
chapter will serve to distinguish the sailing vessel of to-day from
its predecessors of various types, to explain the disappearance of
this form of propulsion and to indicate its few remaining uses.
Thus some of the modern characteristics of water carriers will
be emphasized by contrast with the materials and methods of the
past.

CLASSIFICATION OF SAILING VESSELS

The larger sailing vessels may be grouped in classes according
to " rig " or arrangement of sails, the number of masts, and the
form or shape of hull. The principal methods of rigging are the
" square rig " and the " fore-and-aft rig/' though in small sailing
vessels peculiar variations have been introduced by custom and
convenience. The number of masts has tended to increase with
the increased size of vessels, made possible by improvements in
materials, methods of construction and mechanical handling, until
a maximum of seven has been reached. The subject of form may
be dismissed here with the statement that it developed from the
bluff-bowed vessel with a " beam " or breadth one- fourth of its
length, as illustrated in the English vessels in the West Indian

3



MERCHANT VESSELS



trade o '$ie ; eaVty' -nineteenth century, to the narrower schooner
and " clipper " ship, with concave water lines at the bow, beam
only one-fifth or one-sixth the length and relatively great breadth
well aft. Other developments in form of hull are discussed later.

A *' square-rigged " vessel is one with the yards supporting
square sails extending across the masts, approximately equal
lengths of yard and equal sail areas extending on each side. The
following illustration of a full-rigged ship shows the arrangement,
some subsidiary sails being added jibs, staysails and spanker.

In the " fore-and-aft " rig the yards and booms do not cross




Reproduced by permission from A. M. Knight, " Modern Seamanship,"
Van Nostrand Co., N. Y.

FlG. I. FULL RIGGED SHIP

the mast but extend on one side only, the sails therefore not being
square but tending to approach a triangular form. The yards
and booms move with one end resting on the mast as a pivot.
Figure 2, a modern schooner, will serve as an illustration.

Various combinations of these two styles of rigging on vessels
with one or more masts produced the types : ( I ) ship, with three
or more masts, all square-rigged; (2) bark, with three or more
masts, all masts except the after-mast square-rigged; (3) barken-
tine, with three or more masts, the two after-masts fore-and-aft
rigged; (4) brig, with two masts both square-rigged; (5) brigan-



METHODS OF PROPULSION 5

tine, a brig without a square mainsail; (6) the sloop, with one
mast fore-and-aft rigged; (7) the schooner, with two or more
masts fore-and-aft rigged. The last-named is the sailing vessel
type of primary importance to-day.

The schooner has steadily increased in size, owing largely to
the introduction of machinery for hoisting and lowering sails and




Reproduced by permission from Spear's " Story of the American Merchant Marine,"

Macmillan, 1915

FIG. 2. SCHOONER Thomas W. Lawson

anchors, until in 1902 the Thomas IV. Lawson, a seven-masted
steel schooner of 5218 tons gross register was launched. This
vessel had a spread of 43,000 square yards of canvas and was
manned by a crew of 18. In 1890 an i8oo-ton vessel with five
masts was considered large and until the introduction of labor-
saving machinery as low as 900 tons marked approximately the
limit of size. The schooner has usually a greater proportionate
beam than the steamer, a high freeboard or distance from water
line to deck, great sheer (curvature of deck) forward, and an un-
obstructed deck from forecastle to bridge, which is located well



6 MERCHANT VESSELS

aft (see illustration, page (5). Both the square and fore-and-aft
rig have advantages in different winds and weathers, but the
fore-and-aft is more manageable, thus reducing the crew and
operating expenses. It is estimated that the seven-masted
schooner described above, if square-rigged, would require a crew
of 40 men to handle her instead of a crew of 18.

DECLINE IN IMPORTANCE OF THE SAILING VESSEL

But all of the various types of sailing vessels except the
schooner have been driven out by steamers, and the usefulness of



Wor/d^'s Merchant Marine

A/ef /onnoge of Sf earners

and Sf" />ng I/ess f/s




1910 1920



even this form is exceedingly limited. This elimination of the
sailing vessel resulted, not from the unexceptionable superiority
of the steamer, but because the advantages of the latter out-
weighed the good features of the former. Thus, in some trades,
such as to the Far East, the competition between the two was
keen for a comparatively long time and only great improvements
in steam propulsion finally gave it supremacy.

By reference to the above diagram it will be seen that the
sailing vessel, as regards the world's merchant marine, could not
maintain its position after 1880. In 1860 sailing vessels con-



METHODS OF PROPULSION 7

tributed 89 per cent of the total tonnage; in 1870, 81 per cent;
in 1880, 71 per cent; and by 1890, only 53 per cent. At the
present time sailing vessels form less than 10 per cent of the
total tonnage of the world, and even this figure exaggerates their
importance because of the many insignificant vessels which are
included to form this aggregate.

In spite of the impulse which the development of early steam













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I&30 1840 1850 I860 1870 I860 1890 1900 1^0 19

FIG. 4



navigation received in the United States we continued longer than
foreigners to attempt to use the sailing vessel as a competitor of
steam, as illustrated by the above diagram. Thus, in world
commerce in 1900, 32 per cent of the tonnage was sail, while over
49 per cent of American tonnage was still propelled in this man-
ner. To put it in another way, the world fleet was composed al-
most equally of steam and sail tonnage shortly after 1880, while
American steam tonnage did not equal sail until nearly 1899.
The facts are equally well stated by saying that the sail tonnage
of the United States has declined more slowly than that of the
world, but wie have not kept pace in the acquisition of steam
vessels.



MERCHANT VESSELS



ADVANTAGES OF STEAM OVER SAIL

It will throw some light upon the nature of present-day com-
merce to indicate the reasons for the supplanting of sail by steam.

i. The Superior Regularity of Steam-Propelled Vessels. In
the early days of steam vessels they were subject to great handi-
caps because of the inferior nature of the engines utilized for the
work and the consequent heavy consumption of fuel. It is a
mistake to suppose that the steamer everywhere outstripped the
sailing vessel; the latter held its own on some routes for years.
But one manifest advantage possessed by the steamer, in spite
of its deficiencies, was that of regularity. A sailing vessel might
make the voyage from London to Australia in 60 days with a good
passage, but, on the other hand, it was equally likely that the trip
would consume half again as much time. The date of the sailing
vessel's arrival was purely a matter of conjecture, and commercial
projects .based upon it were therefore merely tentative in nature.
As an illustration, in the cotton business 45 years ago the con-
tracts were entirely for delivering the product " on the spot " and
"on arrival." A contract for delivery by some definite future
date, such as now constitutes the majority of transactions, was an
impossibility, because of transportation conditions. A little later


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