Total Number of Engines Built	98*
First Engine Built	1889
Last Engine Built	1919*
First Engine Written Off	1903
Last Engine Written Off	1934

31/12/00	31/12/10	31/12/20	31/12/30	31/12/40
92	61	15	5	–

Notes

* Six engines were obtained from Chillagoe Railway and Mining Coy after its collapse. These engines were designed to provide an engine more powerful than the B13 class. A number of different features were introduced to various batches of this class. The first fifteen engines built by Nasmyth-Wilson had British style “pull over” regulators, separate regulator and safety valve domes on the boiler and spartan cabs but no air brakes. The second batch of engines, constructed by Evans Anderson Phelan, were fitted with an enclosed cab with glass windows on the spectacle plate, American style “pull out” regulator and Westinghouse Brakes. These engines also had steel boilers in place Yorkshire iron used on the earlier batch. This allowed the boiler pressure to be raised to 140 psi. Further improvements were made to the cab on the engines built by Yorkshire Engine Company in 1895. This design of cab became standard on all subsequent engines until the “sedan” cab was introduced in 1935. American Balance slide valves were fitted to all B15 engines built from 1898. The “balanced” valves proved successful and were fitted to all subsequent slide valve engines.

The modifications introduced with various batches were later incorporated into the older engines as they underwent overhaul. The large awing in front of the spectacle plate of earlier cabs disappeared when the new style cabs were fitted. Sand boxes were originally on the running boards but later replaced with the more common sandbox mounted on top of the boiler. As boilers were renewed the safety valves were incorporated into the regulator dome. In 1900, N° 336 was fitted with 45″ coupled wheels to increase the engines speed and so make it suitable for use on passenger trains. The experiment was successful and a further 92 engines were similarly rebuilt. They became known as the “B15 Converted” class to distinguish them from the original designed engines. The five engines that did not undergo conversion were all condemned in 1934. This class was sometimes referred to as “B15 Goods”.

Builder	Price
Evans, Anderson, Phelan	£2,119
Yorkshire Engine Company	£2,119
Walkers Limited	£2,397/10/10*

* Average price for first 30 constructed

Abbreviations

NW – Nasmyth, Wilson & Co, Manchester, UK
EAP – Evans, Anderson, Phelan & Co, Brisbane, Qld
York – The Yorkshire Engine Co, UK
Walkers – Walkers Ltd, Engineers, Maryborough, Qld
WO – Written off Register

INTRODUCTION

Queensland was separated from New South Wales on 6 th June 1859 when Queen Victoria signed Letters Patent. At that time the colony had a European population of only 25,000 spread over an area 670,500 square miles (1736587 sq km). The new government was faced with the daunting task of providing the necessary services. Limited income together with a heavy capital works programme caused it to struggle financially in the early years. The parliamentarians were aware that railways had revolutionised transport elsewhere in the world and realized that such a system would encourage inland settlement and development. Mr Macalister, Secretary for Lands and Works, introduced the first Railway Bill into Parliament on 19 th May 1863 . That initial goal, coupled with financial restraints, was to influence railway development in the state for the next century.

The first railway in Queensland from Ipswich to what is now known as Grandchester opened on 31 st July 1865 . Work commenced on a line from Rockhampton while the railway from Grandchester gradually extended westwards. Another undertaking was commenced from Townsville in 1880. Lines were progressively extended inland from the ports as part of the government’s policy. Eventually, eleven isolated state government railways were established and these together with four local government shire tramways and the privately owned Chillagoe Railway became the Queensland Government Railways. All with the exception of the Normanton and (now closed) Cooktown railways were eventually linked together. The process was slow and the North Coast Line was not completed until 1924. The system’s expansion came to a halt in the Great Depression. It would be more than two decades before another new railway was constructed.

At the outbreak of World War 2 there was a network of 6,500 miles (10,400km), second only in length to South Africa for 3’6 ” gauge railways. Unfortunately, much of it was built cheaply and consequently was of light construction with sharp curves, steep grades and minimal ballast. Only 1% consisted of 80lb (40kg) rail and half the system was laid with lighter than 60lb (30kg) rails. Numerous timber trestle bridges also existed and these imposed severe axle load restrictions which was a restraint on locomotive sizes. Nevertheless, the railway generally satisfactorily served its purpose at the time. Distant communities and rural industries wanted frequent services and politicians were determined that ‘their’ railway would provide them. After all, the politicians’ future existence relied on keeping their voters happy. This political interference caused many trains to run at frequencies and to places that were not economically justified. Ironically, some of those same politicians that demanded frequent and, at times, subsidised services for their constituents were also the ones who could be heard on other occasions bemoan the financial drain that the railway was on Treasury. The lightly laid track was adequate in most cases to handle the available loading. Other than during the hectic years of World War 2, only on a few busy lines such as sections of North Coast Line and Main Line to Toowoomba was there evidence of deficiencies and required trains to be regularly double-headed and banked over range sections. Not surprisingly these places were where the early diesels did most of their work.

The railway was in a run down state after World War 2 due to deferred maintenance and many locomotives and items of rollingstock, that would have otherwise been retired, had been kept in service to handle the huge demands. A massive rehabilitation programme was instituted to overcome these problems and orders were placed for new locomotives and rollingstock. In 1948, the Chief Mechanical Engineer recommended that the purchase of diesels be investigated. Fiscal restraints of the late 1940s and early 1950s no doubt had some bearing on the small size of initial purchases. Also, probably railway officials were reluctant to place large orders until they established what types would be most suitable for local requirements. History later proved that this ‘wait and see’ philosophy was justified as the twelve (what later were called) 1170 Class DEL , obtained in 1957/58, did not live up to expectations.

Development of the export coal market started a huge upsurge in traffic in the mid 1960s (one that has continued through to today) and was the catalyst that launched the system into a massive modernization and upgrading programme. Many uneconomic branch lines were closed and by 30 June 1970 there were 389 diesels but only 15 steam engines on the register. Improvements have continued since then and today QR is a modern competitive railway, a far cry from what it was 50 years ago.

LOCOMOTIVE DEVELOPMENT

The early railway had a distinctly English flavour with its officials, locomotives and rollingstock being imported from Britain . In 1870s the Baldwin Locomotive Works in USA was advertising that they could provide cheaper locomotives than British manufacturers. This was sufficient incentive to break Empire ties and three engines were imported from America in 1877. Several more were obtained over the next seven years until increasing government pressure to support local or British manufacturers resulted in no further acquisitions from America until the AC16 Class in 1943. In fact, by the turn of the century locomotives were only obtained from outside the state when local manufacturers were unable to supply.

Although early locomotives were mainly the design of their manufacturers, some local modifications and experiments were performed. Most notable of these were extended smokeboxes, deep fireboxes and rocking grates. These successful innovations introduced in 1880s were perpetuated in future designs and in many instances were fitted to earlier engines as they underwent overhaul. Locals recognised suitable features of existing engines and many of these were incorporated into future designs and so Queensland Railways steam locomotives developed into a mix of both British and American practice. The first truly successful local design was the PB15 Class of 1889. It contained a number of features that were to eventually become characteristic of Queensland engines. Probably the most prominent of these was the “Baldwin” style sandbox mounted on top of the boiler. This had first appeared on A12 engines imported in 1882 and continued to be incorporated in new locomotives until 1953 when the last C17 was delivered.

Engineers kept abreast with developments elsewhere and these were tried and if found suitable adopted. Tests were carried out with both vacuum and air brakes as early as 1877. Initially vacuum was considered the most suitable and adopted. However improvement to the Westinghouse air system caused fresh trials to be conducted in 1889. These proved the air brake to be superior and so it became standard although previous fitted vacuum stock continued to operate for some time. The advantages of Walschaerts valve gear were acknowledged and it was fitted to the 6D16 engines built from 1901 and all future classes, except for the experimental B16½. This engine was equipped with Southern valve gear but that proved to be wanting. Economies from superheating were recognised prior to World War 1. In 1914, C18 N°693 was fitted with a Schmidt type superheater and was the first superheated engine to run on QR. Electric headlights were used on engines on some unfenced lines as early as 1918. By the late 1920’s it became policy to fit electric headlights to all new locomotives except the D17 class which was restricted to running in the Brisbane suburban area. With few exceptions, all steam locomotives remaining in service by 1951 had been so fitted. By 1920s, Queensland enginemen had the benefit of a number of standard features that were not available to their interstate counterparts. These included labour saving devices such as rocking grates, hopper type ashpans with bottom discharge and smokebox ash ejectors. Roller bearings were introduced in 1930s. All steam locomotives built in the 20 th Century, except the AC16 and Garratt Classes, were designed locally. The BB18¼ did however incorporate some alterations suggested by Vulcan Foundry.

Unfortunately, the biggest factor influencing locomotive development was finance, or more correctly the lack of it. Government policy prescribed that loan monies were required for all new work while maintenance costs were charged against operating revenue. Thus the Railway Department was reliant on parliament for funding. This firstly affected the building of new lines. Politicians were keen to expand the railway at minimum cost and consequently construction standards were often as cheap as possible resulting in the use of light rails, little or no ballast, minimum earthworks, sharp curves and numerous timber bridges. Timber was abundant in most areas and before the days of heavy earthmoving equipment is was quicker and cheaper to build a timber bridge than to construct an embankment. Draughtsmen and engineers constantly had to struggle to design more powerful locomotives yet remain within the constraints imposed by the standards of the permanent way. One method of increasing power was to use small coupled wheels but that tactic reduced the locomotives’ maximum capable speed. Conversely, larger coupled wheels enabled greater speed but resulted in a less powerful locomotive. In the latter part of the 19 th Century, the administration, like many overseas counterparts, were acquiring two types of locomotives; more powerful ones with smaller coupled wheels for goods work and others with larger coupled wheels for faster passenger work. Increasing mail train loads soon grew beyond the capacity of the faster passenger engines. Designers then looked towards creating a ‘mixed traffic’ locomotive with sufficient power to haul useful loads yet with coupled wheels sufficiently large to enable handling passenger trains at reasonable speeds. These goals set the design criteria for most classes produced in the 20th Century. The PB15 with its 48″ coupled wheels amply fulfilled this role. It was capable of hauling reasonable loads yet its coupled wheels enabled speeds of up to 50 miles per hour. The popular B18¼ Class, introduced in 1926, produced maximum possible power for its adhesive weight and with 51 ” coupled wheels proved more than capable of exceeding permissible track speeds. Still, Queensland locomotives were small by world standards, even when compared with other 3′ 6″ (1067mm) railways. At the end of the steam era in 1970, 12 tons was the highest axle load permitted for steam locomotives on the main line. By way of comparison, this was approximately only two thirds of that allowed by South Africa on their main lines and roughly equivalent to their branch line limit. Financial constraints also inhibited the development of some new designs and even in the case of a few completed designs prevented their production. The most notable example of the latter case was the proposed CC17 Class which was abandoned in 1953, although the successful introduction of diesels also had some bearing on that decision. Funds were also occasionally not forthcoming when additional motive power was required to cater for increasing traffic. This resulted in the regrettable, but necessary, repair of older engines that had reached the end of their economic life. Such repairs being classed as maintenance costs were treated as operating expenses.

Despite these limitations, Queensland’s steam locomotives generally acquitted themselves well when compared with those of other systems.

LOCOMOTIVE CLASSIFICATIONS

An alphabetical system of classification was adopted after 1868. The system was designed to group together engines with similar power ratings to satisfy the Traffic Branch. Apparently in time confusion developed due to, amongst other things, isolated railways applying their own names rather complying with the established method. In a few cases the builder’s name was included as part of the class title. The passenger engines (later A12 class) that were introduced in 1882 never received a class under the system but were always referred to as “American Passenger” . The system became unwieldy and was eventually replaced.

The current classification method was adopted in 1889. Letters are used to identify the number of coupled wheels followed by numerals indicating the cylinder diameter in inches.

A, Four coupled; B, Six coupled; C, Eight coupled; D, Tank Locomotives

In the case of tank engines, the letter D was originally preceded by a figure denoting the number of coupled wheels eg. 6D17. Use of the number prefix was abolished from circa 1937. Where there was more than one type that fell within these guidelines an additional prefix letter was added to distinguish the difference. When a later model of an existing class was introduced the practice was to double the letter eg. BB18¼, CC19, DD17. In other cases where differences existed a different additional letter was added. In the case of the AC16 Class, the A indicates American while with the PB15 Class, P indicates Passenger. The unusual step was taken in 1924 when an ‘ improved ‘ version of the PB15 class was introduced by denoting it by the addition of the year to the normal classification i.e. PB15 1924. In later years, at least, the year was rarely shown on locomotives. Another exception to the normal rule was when members of the original B15 Class were altered. These engines were referred to as B15 Converted, which for marking purposes was usually shown as B15 Con. Australian Standard and Beyer Garratt Locomotives were not given a classification code. A major deficiency of the system was that it did not distinguish locomotives within these classes that had altered features such as roller bearings, larger tenders or improved braking.

The classification code was painted on the left hand side of the front headstock.

There were shortened versions of some of these classifications in common usage: ‘ B18 ‘ for (B)B18¼, ‘ D’ for D17, ‘ DD ‘ for DD17, ‘PB’ for PB15 and ‘ Garratt ‘ for both types. At times these abbreviated names were used in official documents. Another term that received some use in the 1960’ s was ‘ Standard Class Locomotive ‘ . This was occasionally used in Train Notices etc. to identify a B18.

In addition to these titles, many were commonly referred to by nicknames;

‘Bety’ (from telegraphic code word)	BB18¼
‘Yank’	AC16
‘Limousine’	C17 with sedan cab
‘Brown Bomber’	Roller Bearing C17 painted brown
‘Walschaerts’	1924 PB15
‘Black Tank’	D17
‘Blue Tank’ or ‘Blue Baby’	DD17
‘Deep Sea Liner’ or ‘Bull’	C19

UNIT LENGTHS

At times it was necessary to identify the length of a particular train. It was essential on single lines to know if a crossing loop had the capacity to accommodate a train clear of the main line. A system of ‘ unit lengths ‘ was established to enable easy calculation of train lengths. The unit was based on the length of a standard F wagon, 17 ‘ 6 ” (5.33 metres). Train lengths were then referred to as the equivalent of ‘ xx ‘ F. Later the letter ‘ F’ was omitted and the term ‘units’ applied solely. The length classification was marked on vehicles (except suburban carriages and rail motor stock) and locomotives to enable train lengths to be easily computed.

The unit length was altered to 5 metres after introduction of Metric measurements

All steam locomotives still in service after 1 st February 1966 received the marking on the front buffer beam adjacent to the class designation. The length classification number was stencilled in 1¾” figures enclosed in a 4 ” diameter ring.

Class	Length Classification
D17	2.2
DD17	2.3
PB15	2.8
C16 and C17	3.1
B18¼ and AC16	3.4
BB18¼	3.5
Beyer Garratt	5.2

DEPOT AND DIVISION MARKINGS

Commencing in the late 1920 ‘ s, locomotives were marked with their depot and Division. Both were generally recorded on the rear of the tender with the depot identification being also shown on the right hand side of the front headstock. From the late 1940 ‘ s, these marking were omitted from metropolitan (Mayne, Wooloongabba and Ipswich ) engines and later by other SED depots. In the Central Division, the depot was not normally shown on the tender. The Beyer Garratts, when attached to Rockhampton, had that depot ‘ s markings on both front and rear headstocks but no divisional markings.

South Eastern Division

SED

B	–	Brisbane (i.e. Mayne)
G	–	Gympie
I or Ip	–	Ipswich
M	–	Maryborough
NB	–	North Bundaberg
SB	–	South Brisbane (i.e. Wooloongabba)

Central Division

CD

A	–	Alpha
E	–	Emerald
Mk	–	Mackay
Mt	–	Mount Morgan (closed 1952)
R	–	Rockhampton

Northern Division

ND

C	–	Cairns
CT	–	Charters Towers
Cy	–	Cloncurry
H	–	Hughenden
T	–	Townsville

South Western Division

SWD

R	–	Roma
T	–	Toowoomba (Willowburn)
W	–	Warwick

Administrative Divisions of QGR

In 1878, it was decided to group the existing and proposed railways into three divisions: – Southern, Central and Northern. The Southern Division was later split into two parts. The following lists and describes the arrangement that existed during the latter part of the steam era.

South Eastern Division

Main line and Branches between Brisbane and Helidon

North Coast Line and Branches between Brisbane and Avondale

South Western Division

Main line between Helidon and Toowoomba

All lines south and west of Toowoomba.

The South Western Division was amalgamated with the South Eastern Division to form the Southern Division in 1984.

Central Division

North Coast Line and Branches between Avondale and Bloomsbury

Mackay Railway

Central Railway and Branches between Rockhampton and Winton

Northern Division

North Coast Line from Bloomsbury to Cairns

Townsville to Mount Isa and Winton

Cairns Railway

Normanton Railway

LOCOMOTIVE NUMBERS

The entire Locomotive Branch was placed under the control of a newly created position of Locomotive Engineer in 1883. By the end of the decade this title was changed to Chief Mechanical Engineer (CME) and again later to Chief Mechanical Engineer and Workshops Superintendent (CME&WS). In conjunction with several other rearrangements, locomotives and rollingstock were consolidated into one rollingstock register in 1889-90. This resulted in most items, except those operating on the original Southern and Western Railway (from Ipswich ), being renumbered.

After 1889, numbers were applied chronologically in blocks as orders for construction were issued. The outcome was, when contracts for construction of different classes were being placed simultaneously, that groups of numbers for one class appeared between blocks of numbers allocated to another. Additionally, if the delivery of engines under a contract was delayed, it could result in engines entering service not in numerical sequence. E.g. BB18¼ 1089 entered service in March 1958 but Beyer Garratt 1090 had entered traffic in May 1951.

During the period from 1910 to 1935 there was also a practice to re issue numbers from locomotives that had been written off the register. Not all numbers were reused. The highest number to be ‘ recycled ‘ was 340. AC16 engines retained their US Army numbers with the suffix ‘ A ‘ added to distinguish them from existing locomotives that had otherwise identical numbers. Australian Standard Garratts retained the numbers allocated to them by the Commonwealth Land Transport Board.

Builders and Number Plates

Builder ‘ s Plates were supplied by the manufacturer to their own design. Most were oval shaped, but a few companies opted for different styles. Possibly the most impressive were those on engines supplied by Clyde Engineering Works, Granville NSW. Engines built by Dubs & Co, Glasgow carried an elongated diamond shape plate. Walkers Ltd used oval plates but reduced their size in later years. Those engines supplied by Baldwin in both centuries had round ones. With the exception to the Baldwin built engines, where they were attached to the smokebox, builder ‘ s plates were normally affixed to the cab sides. Some B15 engines constructed by Evans, Anderson, Phelan and Walkers Ltd had additional plates fitted to the tenders. Early engines manufactured by Walkers also had a large circular plate incorporating a star and the company’ s name affixed to the centre of the smokebox door. The first five C16 engines and the six 6D13½ Class engines built at Ipswich had a combined builder ‘ s and number plate on the cab sides. The ASG engines built at VR ‘ s Newport Workshops were not fitted with builder ‘ s plates. It has been said that the VR CME refused to allow them to be fitted lest he be held responsible for the engines (and their defects).

Number plates were rectangular in shape and generally attached to the first ring of the boiler on tender engines and to the sides of the bunker on tank engines. Those on the 6D13½Abt engines were attached to the smokebox. The ASGs carried a CLTB number plate on cab sides. AC16 engines were not supplied with number plates. The engine number was painted on the cab side in the usual position for the builder’ s plate. Engines of that class that were based in the Central Division also had the number painted on the boiler where a number plate would normally be attached. The PB15 engine, N°12, purchased from Aramac Shire Council in 1958 was not fitted with a number plate but had the number painted on the boiler where number plates would normally be affixed. Prior to 1929, except on the 6D13½ Abt engines, number plates also carried ” N°” in advance of the numerals. Number plates and most builders ‘ plates were made of brass with their background painted red except for the roller bearing C17s where it was green. Baldwin builder’ s plates attached to smokeboxes were painted black.

Naming of Locomotives

The first four engines imported into Queensland were given names but thereafter engines were normally only issued with numbers. The next engines to received names were C18s (later CC19s) N°693 and N°694 when, in 1915, they were named Sir William MacGregor and Lady MacGregor after the then Governor of Queensland and his wife. In 1923, C19 N°702 was named as “Century ” as it was the 100 th engine constructed at Ipswich Workshops. Several of the Ipswich Workshops shunt engines were called ” Pompey” during their tenure. In recognition of this, a name plate was fitted to the front of the last steam incumbent B13½ N°398. When DD17 N°1051 was restored to working order it was named ” The Blue Baby ” and fitted with a name plate. Since their introduction, various DELs have been given names.
{mospagebreak title=Liveries}

LIVERIES

Some PB15 class engines were painted Quaker green prior to WW1. Three early C16s were specially painted (N° 427 chocolate, N° 428 royal blue and N° 429 green) for working the Sydney Mail Train. Smokeboxes were black japanned. From then until the batch of B18¼ engines built in 1936-37, the clothing of boilers, cylinders etc. was planished mild steel sheet of a light blue colour. Engine buffer beams were painted signal red from 1935.

By 1940, all engines were painted black enamel with red buffer beams, builder ‘ s and number plates. Brass boiler bands were not painted. Some brass dome covers were also not painted or had previously applied paint removed. The canvas cover on timber cab roofs was painted black until 1952, when red oxide was substituted. The steel cab roofs on BB18¼, DD17 and Beyer Garratts were painted black.

The following liveries were introduced in 1949: –

B18¼/BB18¼	–	Hawthorne Green and carmine red trim
C17	–	Chocolate brown and willow green trim
DD17	–	Royal blue, later midway blue, and red trim
Beyer Garratt	–	Midland red and chrome yellow trim.

BB18¼ class entered service in the new colours and B18¼ engines were gradually repainted green, commencing with N°50 and N° 911 in 1949. DD17 N°949 entered service painted black in 1948. The next engine, N°950, was painted royal blue for exhibition at Queensland Industries Fair in 1949. The remainder of the batch, N°951 & N°954, were also painted royal blue when they entered service in 1949. N°949 was subsequently repainted to conform to the new colour scheme. The next batch, N°1046 & N°1051, entered service painted midway blue. The first six engines were later repainted in this colour.

It was intended that only the roller bearing C17s (N°961 & N°1000) were to be painted brown. However, several older engines also received this treatment. Instructions were subsequently issued that this colour scheme was to be restricted to roller bearing engines. Those earlier engines that had been repainted brown then reverted to standard black.

Some non standard features appeared at different times (B18¼ N°50 had blue trim in its final days) Central Division engines had the steam end of WH pumps painted red & green in case of roller bearing C17s.

Tyre walls were painted white at various times.

In conjunction with the phasing out of steam, engines receiving workshop attention from 1967 were painted in standard black enamel with red trim. This resulted in several B18¼, BB18¼ and roller bearing C17 engines returning to service in black livery. No DD17 or Beyer Garratt engines were affected by this policy.

CLASS DESCRIPTIONS

Separate descriptions are provided for all classes of steam locomotives that operated on QGR during the 20 th Century. These contain notes on each class together with their principal dimensions and lists of the numbers built, when they entered service and were finally written off. Wheel arrangements are identified using the Whyte method. This system was designed by Frederic Whyte and became standard in UK , USA and Australia whilst some European railways adopted another method. Under the Whyte system 4-6-0 = ooOOO etc. Some wheel arrangements were also given names eg Mikado for 2-8-2 and Pacific for 4-6-2 . Tank engines are identified by the letter ‘ T ‘ appearing after the arrangement. The majority of the information is self explanatory but the following are brief descriptions of Adhesive Weight, Axle Loads, Superheating, Tractive Effort and Written Off.

Adhesive Weight and Factor of Adhesion

For a steam locomotive to have good adhesion, it is important to have sufficient weight on the coupled wheels. The weight bearing on the coupled wheels is called Adhesive Weight. This weight divided by the tractive effort is called the factor of adhesion. It has been found that a factor of adhesion of around 4 is a good balance of pulling force and engine weight.

A locomotive will be “slippery ” if the factor of adhesion is low (less than four). Because of the general weight and axle load restrictions imposed on QR engines, the B18¼, BB18¼ and C17 classes particularly suffered from low adhesion. This resulted in their full theoretical tractive effort not being available. Consequently their scheduled loads were less than had that been the case.

Axle Loads

Axle loads indicate the maximum weight present on any axle. These amounts are expressed in tons. That load and the overall weight dictated on which lines the locomotives could operate. Basically, lines were divided into three categories.

Main lines were laid with 60lb or heavier rails and capable of supporting a 12 Ton Axle Load (TAL) and the heaviest steam locomotives.

The next strongest lines were generally known as C16 standard lines. Some of these contained 60lb rails but many were laid with 41¼ or 42lb rails. At first they had a limit of 8 tons but over the years this was progressively increased to 8.25, then 8.9 and finally 9.25 TAL. They were available for C16, C17 and AC16 (fitted with a C16 tender) engines.

Light branch lines were originally only available for B13 Class engines could carry a 7 TAL but this was later increased to 8 tons and they were usually referred to as B15 standard lines. They were all laid with 41¼ or 42lb rails. They were available for B15 and PB15 engines.

The Etheridge and Normanton Railways were of a lighter standard although the former was upgraded after the demise of steam.

The reciprocating motion of a steam locomotive causes a ” hammer blow” effect on the track and bridges. This is not present with Diesel Electric Locomotives and thus heavier axle loads are allowed with that type of motive power. E.g. lines available to 12TAL steam were suitable for 15TAL DEL.

In some instances, bridges imposed more severe restrictions than the remaining track structure and were the limiting factor particularly in relation to running of attached engines.

Superheating

Superheated steam has less water vapour and will therefore not condense as rapidly as ‘wet’ or saturated steam. Its use leads to substantial savings in coal and water comsumption. Superheated steam is produced by passing steam through a superheater after its production in the boiler. The equipment consists of a header, containing two portions, mounted in the smokebox next to the tube plate. One portion collects saturated steam from the internal steam pipe and from there passes the steam through a series of elements situated inside the larger flue tubes of the boiler. The steam ‘ s temperature is raised during this passage and it is collected in the other portion of the header. From there it passes through pipes to the steam chests. The process does not affect the pressure of the steam but raises its temperature by 130°C, or more in favourable circumstances.

Tractive Effort

Tractive effort is a theoretical quantity. Railways preferred to use it for steam locomotives rather than horsepower ratings because horsepower involved a time quantity which was determined, in part, by how well the locomotive was being fired (among many other variables). Tractive effort, on the other hand, was decided strictly by the geometry of the locomotive. Tractive effort is calculated by the standard Phillipson formula:

Tractive Effort	=	d² X S X BP*
		D

Where: –	d	= Diameter of Cylinder (inches)
	S	= Stroke of Piston (inches)
	BP	= Boiler Pressure (psi)
	D	= Diameter of Driving Wheels (inches)

*For superheated engines 85% of BP is used in calculations

*For saturated engines 80% of BP is used in calculations

*For some 19 th century engines only 70% of BP was used in calculations

The truly available tractive effort will not generally exceed one quarter of the adhesive weight.

Written Off

All locomotives and rollingstock were recorded as assets in a register. The term ” Written Off ” or ” Written off the Books ” was used to describe them being removed from that record. This inventory was maintained for accounting purposes and there were occasions where engines had been out of service for considerable time before they were removed from the register. This particularly applied to some engines that were set aside during the Great Depression but were not taken off the books until several years later. Conversely, at the end of the steam era there were incidents of engines being written off while they were still in use. One B15Con was removed in 1942 but repaired and returned to the register in 1943 to be finally written off in 1957. A similar situation occurred with a few C19s in 1950s.

QUEENSLAND RAILWAYS

For most of the 20th Century, the government owned railway in Queensland was known as Queensland Railways (QR), Queensland Government Railways (QGR) or at times simply as the Railway Department. These names were used interchangeably over the years and a similar approach has been used in these texts. The latter title was mainly reserved for internal and government matters.

UNITS OF MEASUREMENT

Since steam locomotives were built and operated when the Imperial system of measurements was used in Australia , these units have been used throughout the tables. For those desiring to convert these figures to Metric units the following table maybe useful: –

1 inch (1″)	=	25.4mm
1 foot (1′ )	=	305mm
1 chain	=	20.117 metres
1 mile	=	1.609 km
1 square foot (sq ft)	=	0.0929 sq metres
1 gallon	=	4.546 litres
1 pound (lb)	=	0.454 kg
1 ton	=	1.016t
1 lb per square inch (psi)	=	6.895 kilopascal

When Decimal Currency was introduced on 14 th February 1966 one pound (£1) converted to $2. Twelve pence (d) equalled one shilling (s) and 20 shillings (s) equalled £1. However, inflation and other issues make conversion of monetary amounts meaningless unless these factors are known and taken into consideration. An amount of one pound, two shillings and six pence was expressed thus: – £1/2/6.