NDA (I) 2018 General Ability Test · Question 123 of 150

Correct — A, Thomas Savery. Savery took out his patent on 2 July 1698 for what he described as a new invention for raising water and occasioning motion to all sorts of mill work by the impellent force of fire — in plain terms, a steam pump for draining mines and supplying towns with water. His machine had no piston at all: steam condensed in a vessel to make a partial vacuum that drew water up, and then steam pressure pushed that water higher. He is the first of the three engine-builders in this list, and the name in the stem is his — he set it out in his book The Miner's Friend, or, An Engine to Raise Water by Fire.

• (b)Thomas Newcomen — Newcomen came next, not first. His atmospheric engine of 1712 used a piston and cylinder and avoided the dangerously high-pressure steam Savery's design needed, which made it far more usable in real mines — but it was marketed under Savery's broad patent, and the two men worked in partnership. Fourteen years separate the two machines.
• (c)James Watt — Watt came third, in the 1760s and 1770s, and his contribution was of a different order: the separate condenser made the engine far more efficient, and later refinements converted it from a mere pump into a source of rotary power that could drive factory machinery. That transformation is why his is the name everyone remembers, and why he is the strongest distractor here.
• (d)Richard Arkwright — Arkwright belongs to textiles rather than to steam. His water frame of 1769 spun strong cotton yarn and he is associated with the rise of the factory system, but he built no steam engine.

The steam engine was not invented once but improved in stages, and each stage answered a defect in the one before. Savery's pump could raise water but only from shallow depths and at the cost of dangerous pressures. Newcomen's atmospheric engine, with a piston working under atmospheric pressure, was safe and reliable but wasteful of fuel, since the same cylinder was heated and cooled on every stroke. Watt's separate condenser removed that waste, and once rotary motion was added the engine could drive machines rather than only lift water — which is when steam moved out of the mine and into the factory.

A point of accuracy that a careful student should hold alongside the textbook line. The date 1698 is right — that is the year of the patent — but the phrase 'The Miner's Friend' comes from the title of the book Savery published in 1702 to describe and promote his engine. The paper's compressed sentence is the standard schoolbook version and the answer it wants is unambiguous; the underlying chronology is simply a little richer than the one line suggests. The practical way to prepare this topic is to memorise the sequence rather than isolated names: Savery in 1698, Newcomen in 1712, Watt from the 1760s. Once the order is fixed, any item that supplies a date or an order of precedence solves itself, and the textile inventors — Hargreaves, Arkwright, Crompton, Cartwright — can be kept in a separate list of their own.

• Savery patented his steam pump on 2 July 1698 for draining mines and supplying water.
• His book The Miner's Friend, or, An Engine to Raise Water by Fire appeared in 1702.
• Newcomen's atmospheric engine of 1712 introduced the piston and cylinder and was marketed under Savery's patent.
• Watt's separate condenser made the engine efficient, and later rotary motion turned it into a source of factory power.

• Answering James Watt to any steam engine question because his is the famous name.
• Placing Newcomen before Savery — the atmospheric engine came fourteen years later.
• Mixing the steam inventors with the textile inventors, since both belong to the same decades.

NDA sets one inventor-to-invention item per paper on this period, sometimes as a single name and sometimes as a statement code with dates attached.

• practice — not a real PYQ

  The atmospheric steam engine of 1712, which used a piston working in a cylinder, was built by

  • (a)Thomas Savery
  • (b)Thomas Newcomen
  • (c)James Watt
  • (d)Matthew Boulton

  Answer(b) Thomas Newcomen — his engine followed Savery's pump and preceded Watt's improvements.

• practice — not a real PYQ

  James Watt's most important single improvement to the steam engine was

  • (a)the safety valve
  • (b)the separate condenser
  • (c)the high-pressure boiler
  • (d)the water frame

  Answer(b) the separate condenser — it stopped the cylinder from being heated and cooled on every stroke and transformed the engine's efficiency.