The cylinder is the power-producing element of the steam engine powering a steam locomotive. The cylinder is made pressure-tight with a piston. Cylinders were cast in cast iron and in steel; the cylinder casting includes other features such as mounting feet. The last big American locomotives incorporated the cylinders as part of huge one-piece steel castings that were the main frame of the locomotive. Renewable wearing surfaces were provided by cast-iron bushings; the way the valve controlled the steam entering and leaving the cylinder was known as steam distribution and shown by the shape of the indicator diagram. What happened to the steam inside the cylinder was assessed separately from what happened in the boiler and how much friction the moving machinery had to cope with; this assessment was known as "engine performance" or "cylinder performance". The cylinder performance, together with the boiler and machinery performance, established the efficiency of the complete locomotive; the pressure of the steam in the cylinder was measured as the piston moved and the power moving the piston was calculated and known as cylinder power.
The forces produced in the cylinder moved the train but were damaging to the structure which held the cylinders in place. Bolted joints came loose, cylinder castings and frames cracked and reduced the availability of the locomotive. Cylinders may be arranged in several different ways. On early locomotives, such as Puffing Billy, the cylinders were set vertically and the motion was transmitted through beams, as in a beam engine; the next stage, for example Stephenson's Rocket, was to drive the wheels directly from steeply inclined cylinders placed at the back of the locomotive. Direct drive became the standard arrangement, but the cylinders were moved to the front and placed either horizontal or nearly horizontal; the front-mounted cylinders could be placed either outside. Examples: Inside cylinders, Planet locomotive Outside cylinders, GNR Stirling 4-2-2In the 19th and early 20th centuries, inside cylinders were used in the UK, but outside cylinders were more common in Continental Europe and the United States.
The reason for this difference is unclear. From about 1920, outside cylinders became more common in the UK but many inside-cylinder engines continued to be built. Inside cylinders give a more stable ride with less yaw or "nosing" but access for maintenance is more difficult; some designers used inside cylinders for aesthetic reasons. The demand for more power led to the development of engines with four cylinders. Examples: Three cylinders, SR Class V, LNER Class A4, Merchant Navy class Four Cylinders, LMS Princess Royal Class, LMS Coronation Class, GWR Castle Class On a two-cylinder engine the cranks, whether inside or outside, are set at 90 degrees; as the cylinders are double-acting this gives four impulses per revolution and ensures that there are no dead centres. On a three-cylinder engine, two arrangements are possible: cranks set to give six spaced impulses per revolution – the usual arrangement. If the three cylinder axes are parallel, the cranks will be 120 degrees apart, but if the centre cylinder does not drive the leading driving axle, it will be inclined, the inside crank will be correspondingly shifted from 120 degrees.
For a given tractive effort and adhesion factor, a three-cylinder locomotive of this design will be less prone to wheelslip when starting than a 2-cylinder locomotive. Outside cranks set at 90 degrees, inside crank set at 135 degrees, giving six unequally spaced impulses per revolution; this arrangement was sometimes used on three-cylinder compound locomotives which used the outside cylinders for starting. This will give evenly spaced exhausts. Two arrangements are possible on a four-cylinder engine: all four cranks set at 90 degrees. With this arrangement the cylinders act in pairs, so there are four impulses per revolution, as with a two-cylinder engine. Most four-cylinder engines are of this type, it is cheaper and simpler to use only one set of valve gear on each side of the locomotive and to operate the second cylinder on that side by means of a rocking shaft from the first cylinder's valve spindle since the required valve events at the second cylinder are a mirror image of the first cylinder.
Pairs of cranks set at 90 degrees with the inside pair set at 45 degrees to the outside pair. This gives eight impulses per revolution, it increases weight and complexity, by requiring four sets of valve gear, but gives smoother torque and reduces the risk of slipping. This was unusual in British practice but was used on the SR Lord Nelson class; such locomotives are distinguished by their exhaust beats, which occur at twice the frequency of a normal 2- or 4-cylinder engine. The valve chests or steam chests which contain the slide valves or piston valves may be located in various positions. If the cylinders are small, the valve chests may be located between the cylinders. For larger cylinders the valve chests are on top of the cylinders but, in early locomotives, they were sometimes underneath the cylinders; the valve chests are on top of the cylinders but, in older locomotives, the valve chests were sometimes located alongside the cylinders and inserted through slots in the frames. This meant that, while the cylinders were outside, the valves were inside a
A Cornish engine is a type of steam engine developed in Cornwall, England for pumping water from a mine. It is a form of beam engine that uses steam at a higher pressure than the earlier engines designed by James Watt; the engines were used for powering man engines to assist the underground miners' journeys to and from their working levels, for winching materials into and out of the mine, for powering on-site ore stamping machinery. Cornwall has long had tin and other metal ore mines, but if mining is to take place at greater depths, a means of draining water from the mine must be found; this may be done using horse power or a waterwheel to operate pumps, but horses have limited power and waterwheels need a suitable stream of water. Accordingly, the conversion of coal into power to work pumps was desirable to the mining industry. Wheal Vor had one of the earliest Newcomen engines before 1714, but Cornwall has no coalfield and coal imported from south Wales was expensive; the cost of fuel for pumping was thus a significant part of mining costs.
Many of the more efficient early Watt engines were erected by Boulton and Watt in Cornwall. They charged the mine owners a royalty based on a share of the fuel saving; the fuel efficiency of an engine was measured by its "duty", expressed in the work generated by a bushel of coal. Early Watt engines had a duty of 20 million, ones over 30 million; the Cornish cycle operates. Starting from a condition during operation with the piston at the top of the cylinder, the cylinder below the piston full of steam from the previous stroke, the boiler at normal working pressure, the condenser at normal working vacuum, The pressurized steam inlet valve and low-pressure steam exhaust valves are opened. Pressurized steam from the boiler enters the top part of the cylinder above the piston, pushing it down, the steam below the piston is drawn into the condenser, creating a vacuum below the piston; the pressure difference between the steam at boiler pressure above the piston and the vacuum below it drives the piston down.
Part way down the stroke, the pressurized steam inlet valve is closed. The steam above the piston expands through the rest of the stroke, while the low-pressure steam on the other side of the piston continues to be drawn into the condenser, thereby maintaining the partial vacuum in that part of the cylinder. At the bottom of the stroke, the exhaust valve to the condenser is closed and the equilibrium valve is opened; the weight of the pump gear draws the piston up, as the piston comes up, steam is transferred through the equilibrium pipe from above the piston to the bottom of the cylinder below the piston. When the piston reaches the top of the cylinder, the cycle is ready to repeat; the next stroke may occur or it may be delayed by a timing device such as a cataract. If it was not necessary for the engine to work at its maximum rate, reducing the rate of operation saved fuel; the engine is single-acting, the steam piston is pulled up by the weight of the pump piston and rodding. Steam may be supplied at a pressure of up to 50 pounds per square inch.
Real photos showing the components of the schematical design: The principal advantage of the Cornish engine was its increased efficiency, accomplished by making more economical use of higher-pressure steam. At the time, improvements in efficiency were important in Cornwall because of the high cost of coal. Increasing the boiler pressure above the low atmospheric pressure steam used by James Watt was an essential element of the improvement in efficiency of the Cornish engine; however increasing the boiler pressure would have made an engine more powerful without increasing its efficiency. The key advance was allowing the steam to expand in the cylinder. While James Watt had conceived of the idea of allowing expansive working of steam—and included it in his 1782 patent--, he realized that the low steam pressure of his application made the improvement in efficiency negligible, so did not pursue it. In a Watt engine, steam is admitted throughout the piston's power stroke. At the end of the stroke, the steam is exhausted, any remaining energy is wasted in the condenser, where the steam is cooled back to water.
In a Cornish engine, by contrast, the intake valve is shut off midway through the power stroke, allowing the steam in that part of the cylinder to expand through the rest of the stroke to a lower pressure. This results in the capture of a greater proportion of its energy, less heat being lost to the condenser, than in a Watt engine. Other characteristics include insulation of steam lines and the cylinder, steam jacketing the cylinder, both of, used by Watt. Few Cornish engines remain in their original locations, the majority having been scrapped when their related industrial firm closed; the Cornish engine developed irregular power throughout the cycle pausing at one point while having rapid motion on the down stroke, making it unsuitable for rotary motion and most industrial applications. The Cornish engine depended on the use of steam pressure above atmospheric pressure, as devised by Richard Trevithick in the 19th century. Trevithick's early "puffer" engines discharged steam into the atmosphere.
This differed from the Watt steam engine, which moved the condensing steam from the cylinder to a condenser separate from the cylinder. Tr
Scotland is a country, part of the United Kingdom. Sharing a border with England to the southeast, Scotland is otherwise surrounded by the Atlantic Ocean to the north and west, by the North Sea to the northeast and by the Irish Sea to the south. In addition to the mainland, situated on the northern third of the island of Great Britain, Scotland has over 790 islands, including the Northern Isles and the Hebrides; the Kingdom of Scotland emerged as an independent sovereign state in the Early Middle Ages and continued to exist until 1707. By inheritance in 1603, James VI, King of Scots, became King of England and King of Ireland, thus forming a personal union of the three kingdoms. Scotland subsequently entered into a political union with the Kingdom of England on 1 May 1707 to create the new Kingdom of Great Britain; the union created a new Parliament of Great Britain, which succeeded both the Parliament of Scotland and the Parliament of England. In 1801, the Kingdom of Great Britain and Kingdom of Ireland enacted a political union to create a United Kingdom.
The majority of Ireland subsequently seceded from the UK in 1922. Within Scotland, the monarchy of the United Kingdom has continued to use a variety of styles and other royal symbols of statehood specific to the pre-union Kingdom of Scotland; the legal system within Scotland has remained separate from those of England and Wales and Northern Ireland. The continued existence of legal, educational and other institutions distinct from those in the remainder of the UK have all contributed to the continuation of Scottish culture and national identity since the 1707 union with England; the Scottish Parliament, a unicameral legislature comprising 129 members, was established in 1999 and has authority over those areas of domestic policy which have been devolved by the United Kingdom Parliament. The head of the Scottish Government, the executive of the devolved legislature, is the First Minister of Scotland. Scotland is represented in the UK House of Commons by 59 MPs and in the European Parliament by 6 MEPs.
Scotland is a member of the British–Irish Council, sends five members of the Scottish Parliament to the British–Irish Parliamentary Assembly. Scotland is divided into councils. Glasgow City is the largest subdivision in Scotland in terms of population, with Highland being the largest in terms of area. "Scotland" comes from the Latin name for the Gaels. From the ninth century, the meaning of Scotia shifted to designate Gaelic Scotland and by the eleventh century the name was being used to refer to the core territory of the Kingdom of Alba in what is now east-central Scotland; the use of the words Scots and Scotland to encompass most of what is now Scotland became common in the Late Middle Ages, as the Kingdom of Alba expanded and came to encompass various peoples of diverse origins. Repeated glaciations, which covered the entire land mass of modern Scotland, destroyed any traces of human habitation that may have existed before the Mesolithic period, it is believed the first post-glacial groups of hunter-gatherers arrived in Scotland around 12,800 years ago, as the ice sheet retreated after the last glaciation.
At the time, Scotland was covered in forests, had more bog-land, the main form of transport was by water. These settlers began building the first known permanent houses on Scottish soil around 9,500 years ago, the first villages around 6,000 years ago; the well-preserved village of Skara Brae on the mainland of Orkney dates from this period. Neolithic habitation and ritual sites are common and well preserved in the Northern Isles and Western Isles, where a lack of trees led to most structures being built of local stone. Evidence of sophisticated pre-Christian belief systems is demonstrated by sites such as the Callanish Stones on Lewis and the Maes Howe on Orkney, which were built in the third millennium BCE; the first written reference to Scotland was in 320 BC by Greek sailor Pytheas, who called the northern tip of Britain "Orcas", the source of the name of the Orkney islands. During the first millennium BCE, the society changed to a chiefdom model, as consolidation of settlement led to the concentration of wealth and underground stores of surplus food.
The first Roman incursion into Scotland occurred in 79 AD. After the Roman victory, Roman forts were set along the Gask Ridge close to the Highland line, but by three years after the battle, the Roman armies had withdrawn to the Southern Uplands; the Romans erected Hadrian's Wall in northern England and the Limes Britannicus became the northern border of the Roman Empire. The Roman influence on the southern part of the country was considerable, they introduced Christianity to Scotland. Beginning in the sixth century, the area, now Scotland was divided into three areas: Pictland, a patchwork of small lordships in central Scotland; these societies were based on the family unit and had sharp divisions in wealth, although the vast majority were poor and worked full-time in subsistence agriculture. The Picts kept slaves through the ninth century. Gaelic influence over Pictland and Northumbria was facilitated by the large number of Gaelic-speaking clerics working as missionaries. Operating in the sixth ce
Gresley conjugated valve gear
The Gresley conjugated valve gear is a valve gear for steam locomotives designed by Sir Nigel Gresley, chief mechanical engineer of the LNER, assisted by Harold Holcroft. It enables a three-cylinder locomotive to operate with only the two sets of valve gear for the outside cylinders, derives the valve motion for the inside cylinder from them by means of levers; the gear is sometimes known as the Gresley-Holcroft gear, acknowledging Holcroft's major contributions to its development. The Gresley conjugated gear is an adding machine, where the position of the valve for the inside cylinder is the sum of the positions of the two outside cylinders, but reversed in direction, it can be thought of as a rocking lever between one outside cylinder and the inside cylinder, as is common on 4-cylinder steam locomotives, but with the pivot point being moved back and forth by a lever from the other outside cylinder. If we approximate the motion of each valve by a sine wave — if we say the position of a valve in its back-and-forth travel is proportional to the sine of the "driver angle", once we have set the zero point of driver angle at the position it needs to be for that valve — the mathematics is simple.
The position of the valve, pinned to the long end of the 2-to-1 lever is sin θ, while the positions of the other two valves are supposed to be sin and sin . The position of the short end of the 2-to-1 lever is − 1 2 sin θ —which, it turns out, is midway between sin and sin for any value of θ. So a 1-to-1 lever pivoted on the short arm of the 2-to-1 lever will do the trick. Locomotives with Gresley valve gear must have the three pistons operating at 120 degree intervals. In order for the inside crank to clear the leading coupled axle, the inside cylinder of a locomotive with Gresley valve gear is positioned higher than the outside cylinders and angled downward. To maintain a smooth flow of torque, the crank angles are offset from equal 120 degree spacing to compensate for the angle of the inside cylinder; the resultant timing of the blast from steam exiting the cylinders still gives these three-cylinder locomotives a regular exhaust beat. There were a number of issues with the Gresley gear.
Because the conjugation apparatus was mounted at the opposite end of the valve spindles from the valve gear, as the valve spindles lengthened with the heat of steam in the cylinders the valve timing would be affected, the gear would need to be removed before it was possible to remove valves for maintenance. However, the B17 Class "Footballer"/"Sandringham" 4-6-0s avoided this particular problem by being designed with the conjugated gear behind, rather than in front of, the cylinders; the main difficulty with this valve gear was that at high speeds, inertial forces caused the long conjugating lever to bend or "whip". This had the effect of causing the middle cylinder to operate at a longer cutoff than the outer cylinders, therefore producing a disproportionate share of the total power output, leading to increased wear of the middle big end. Sustained high speed running could sometimes cause the big end to wear enough that the increased travel afforded to the middle piston by the increased play in the bearing was enough to knock the ends off the middle cylinder.
This happened during the 113 miles per hour run of "Silver Fox". Although the problem could be contained in a peacetime environment with regular maintenance and inspections, it proved to be poorly suited to the rigors of heavy running and low maintenance levels of World War II; this gave rise to big-end problems on the centre cylinder connecting rod on the famous A4 class of streamlined Pacifics and many of these locomotives were fitted with a reduced diameter piston and had the inside cylinder sleeved down as a temporary measure. LNER Class A4 4468 Mallard suffered centre cylinder big-end damage during its world record run and was forced to limp back to its depot for repairs afterwards. Gresley's successor at the LNER, Edward Thompson, was critical of this particular valve gear; as well as introducing new two-cylinder designs, he set about rebuilding Gresley locomotives with separate sets of Walschaerts valve gear for each cylinder. Under British Railways ownership, the application of former Great Western Railway workshop practices for precise alignment of the valve gear and in the manufacture and lubrication of the inside big end bearing solved the problems.
Gresley conjugated valve gear was used by the American Locomotive Company under license for the 4-12-2 locomotives built for the Union Paci
The valve gear of a steam engine is the mechanism that operates the inlet and exhaust valves to admit steam into the cylinder and allow exhaust steam to escape at the correct points in the cycle. It can serve as a reversing gear, it is sometimes referred to as the "motion". In the simple case, this can be a simple task as in the internal combustion engine in which the valves always open and close at the same points; this is not the ideal arrangement for a steam engine, because greatest power is achieved by keeping the inlet valve open throughout the power stroke while peak efficiency is achieved by only having the inlet valve open for a short time and letting the steam expand in the cylinder. The point at which steam stops being admitted to the cylinder is known as the cutoff, the optimal position for this varies depending on the work being done and the tradeoff desired between power and efficiency. Steam engines are fitted with regulators to vary the restriction on steam flow, but controlling the power via the cutoff setting is preferable since it makes for more efficient use of boiler steam.
A further benefit may be obtained by admitting the steam to the cylinder before front or back dead centre. This advanced admission assists in cushioning the inertia of the motion at high speed. In the internal combustion engine, this task is performed by cams on a camshaft driving poppet valves, but this arrangement is not used with steam engines because achieving variable engine timing using cams is complicated. Instead, a system of eccentrics and levers is used to control a D slide valve or piston valve from the motion. Two simple harmonic motions with different fixed phase angles are added in varying proportions to provide an output motion, variable in phase and amplitude. A variety of such mechanisms have been devised with varying success. Both slide and piston valves have the limitation that intake and exhaust events are fixed in relation to each other and cannot be independently optimised. Lap is provided on steam edges of the valve, so that although the valve stroke reduces as cutoff is advanced, the valve is always opened to exhaust.
However, as cutoff is shortened, the exhaust events advance. The exhaust release point occurs earlier in the power stroke and compression earlier in the exhaust stroke. Early release wastes some energy in the steam, early closure wastes energy in compressing an otherwise unnecessarily large quantity of steam. Another effect of early cutoff is that the valve is moving quite at the cutoff point, this causes'wire drawing' of the steam, another wasteful thermodynamic effect visible on an indicator diagram; these inefficiencies drove the widespread experimentation in poppet valve gears for locomotives. Intake and exhaust poppet valves could be moved and controlled independently of each other, allowing for better control of the cycle. In the end, not a great number of locomotives were fitted with poppet valves, but they were common in steam cars and lorries, for example all Sentinel lorries and railcars used poppet valves. A late British design, the SR Leader class, used sleeve valves adapted from internal combustion engines, but this class was not a success.
In stationary steam engines, traction engines and marine engine practice, the shortcomings of valves and valve gears were among the factors that lead to compound expansion. In stationary engines trip valves were extensively used. Valve gear was a fertile field of invention, with several hundred variations devised over the years. However, only a small number of these saw any widespread use, they can be divided into those that drove the standard reciprocating valves, those used with poppet valves, stationary engine trip gears used with semi-rotary Corliss valves or drop valves. Slip-eccentric - This gear is now confined to model steam engines, low power hobby applications such as steam launch engines, ranging to a few horsepower; the eccentric is loose on the crankshaft but there are stops to limit its rotation relative to the crankshaft. Setting the eccentric to the forward running and reverse running positions can be accomplished manually by rotating the eccentric on a stopped engine, or for many engines by turning the engine in the desired rotation direction, where the eccentric positions itself automatically.
The engine is pushed forwards to put the eccentric in the forward gear position and backwards to put it in the backward gear position. There is no variable control of cutoff. On the London and North Western Railway, some of the three-cylinder compounds designed by Francis William Webb from 1889 used a slip eccentric to operate the valve of the single low-pressure cylinder; these included Greater Britain and John Hick classes. Gab or hook gear - used on earliest locomotives. Allowed reversing but no control of cutoff. One component of the motion comes from a eccentric; the other component comes from a separate source the crosshead. Walschaerts or Heusinger valve gear - most common valve gear on locomotives externally mounted. Deeley valve gear - fitted to several express locomotives on the Midland Railway; the combination levers were driven, as normal, from the crossheads. Each expansion link was driven from the crosshead on the opposite side of the engine. Young valve gear - used the piston rod motion on one side of the locomotive to drive the valve gear on the other side.
Similar to the Deeley gear, but with deta
Corliss steam engine
A Corliss steam engine is a steam engine, fitted with rotary valves and with variable valve timing patented in 1849, invented by and named after the American engineer George Henry Corliss of Providence, Rhode Island. Engines fitted with Corliss valve gear offered the best thermal efficiency of any type of stationary steam engine until the refinement of the uniflow steam engine and steam turbine in the 20th century. Corliss engines were about 30 percent more fuel efficient than conventional steam engines with fixed cutoff; this increased efficiency made steam power more economical than water power, allowing industrial development away from millponds. Corliss engines were used as stationary engines to provide mechanical power to line shafting in factories and mills and to drive dynamos to generate electricity. Many were quite large, standing many metres tall and developing several hundred horsepower, albeit at low speed, turning massive flywheels weighing several tons at about 100 revolutions per minute.
Some of these engines have unusual roles as mechanical legacy systems and because of their high efficiency and low maintenance requirements, some remain in service into the early 21st century. See, for example, the engines at the Hook Norton Brewery and the Distillerie Dillon in the list of operational engines. Corliss engines have four valves for each cylinder, with steam and exhaust valves located at each end. Corliss engines incorporate distinct refinements in both the valves themselves and in the valve gear, that is, the system of linkages that operate the valves; the use of separate valves for steam admission and exhaust means that neither the valves nor the steam passages between cylinders and valves need to change temperature during the power and exhaust cycle, it means that the timing of the admission and exhaust valves can be independently controlled. In contrast, conventional steam engines have a slide valve or piston valve that alternately feeds and exhausts through passages to each end of the cylinder.
These passages are exposed to wide temperature swings during engine operation, there are high temperature gradients within the valve mechanism. Clark commented that the Corliss gear "is a combination of elements known and used separately, affecting the cylinder and the valve-gear"; the origins of the Corliss gear with regard to previous steam valve gear was traced by Inglis. George Corliss received U. S. Patent 6,162 for his valve gear on March 10, 1849; this patent covered the use of a wrist-plate to convey the valve motion from a single eccentric to the four valves of the engine, it covered the use of trip valves with variable cutoff under governor control that characterize Corliss Engines. Unlike engines, most of which were horizontal, this patent describes a vertical cylinder beam engine, it used individual slide valves for admission and exhaust at each end of the cylinder; the inlet valves are pulled open with an eccentric-driven pawl. In many engines, the same dashpot acts as a vacuum spring to pull the valves closed, but Corliss's early engines were slow enough that it was the weight of the dashpot piston and rod that closed the valve.
The speed of a Corliss engine is controlled by varying the cutoff of steam during each power stroke, while leaving the throttle wide open at all times. To accomplish this, the centrifugal governor is linked to a pair of cams, one for each admission valve; these cams determine the point during the piston stroke that the pawl will release, allowing that valve to close. As with all steam engines where the cutoff can be regulated, the virtue of doing so lies in the fact that most of the power stroke is powered by the expansion of steam in the cylinder after the admission valve has closed; this comes far closer to the ideal Carnot cycle than is possible with an engine where the admission valve is open for the length of the power stroke and speed is regulated by a throttle valve. The Corliss valve gearing allowed more uniform speed and better response to load changes, making it suitable for applications like rolling mills and spinning, expanding its use in manufacturing. Corliss valves open directly into the cylinder.
The valves exhaust plenums. Corliss used slide valves with linear actuators, but by 1851, Corliss had shifted to semi-rotary valve actuators, as documented in U. S. Patent 8253. In this engine, the wrist plate was moved to the center of the cylinder side, as on Corliss engines; this was still a beam engine and the semi-rotary valve actuators operated linear slide valves inside the four valve chests of the engine. Corliss valves are in the form of a minor circular segment, rotating inside a cylindrical valve-face, their actuating mechanism is off along the axis of the valve, thus they have little "dead space" such as the stem of a poppet valve and the entire port area can be used efficiently for gas flow. As the area of a Corliss valve is small compared to the port area, the effects of gas flow generate little torque on the valve axle compared to some other sorts of valve; these advantages have led to the Corliss form of valve being used in other roles, apart from steam engines with Corliss gear.
The Rolls-Royce Merlin aero-engine used a rectangular butterfly valve as a throttle. Gas-flow forces acting asymmetrically on this butterfly could lead to poor control of the power in some circumstances. Late models, from the 134, used a Corliss throttle valve instead to avoid this problem. A common feature of large Corliss engines is one or two sets of narrow gear teeth in the rim of the flywheel; these teeth allow the flywheel to be barred, that is, turned with th