X 
CONTENTS. 
PAGE 
43. No countenance given by Boulton and 
Watt to this charge—nature of their opposi 
tion to Hornblower’s application for an exten 
sion of the term of patent . . . .31 
44. Statement of Watt’s and Hornhlower’s 
respective claims to the discovery and applica 
tion of expansion . . . . .32 
45. Application of expansion hy Watt in 
Cornwall—its limited success . . .33 
46. Cause of this, the low pressure of the 
steam employed ..... ib. 
47. Watt’s proposed equalizing apparatus 34 
48. The double-acting engine . . 35 
49. Watt’s disputes and litigation with the 
Cornishmen . . . . . .36 
50. Infringers of Watt’s patent—Bull . ib. 
51. Use of Hornblower’s double-cylinder 
engine in Cornwall . . . . .37 
52. Hornhlower’s infringement of Watt’s 
patent—action brought against him by the 
patentees . . . . . .38 
53. List of engines erected by Hornblower 
in Cornwall, and amount of patent dues pay 
able by each . . . . . . ib. 
54. Refusal of the licensees to pay patent 
rent pending the law proceedings . . 39 
55. Nature of the arguments brought 
against the patent, and the answers to them . 40 
56. William Murdock . . . .41 
57. Watt’s other assistants . . .42 
THE PERIOB SUBSEQUENT TO THE CLOSE OF WATTS 
CONNECTION WITH THE COUNTY. 1800 TO 1843. 
58. Great improvement in duty effected in 
Cornwall since 1800—means by which this 
has been done . . . . • .43 
59. Great deterioration of the engines 
which immediately followed Boulton and 
Watt’s retirement from the county . . ib. 
60. Projects of Richard Trevithick for the 
use of high-pressure steam, 1806 . . 44 
61. Captain Joel Lean—his improvements 
at Crenver and Oatfield mines . . .45 
62. The monthly reports of duty established 
by Captain Lean, 1811 . . . .46 
63. Duty of the engines from 1800 to 1814 47 
64. Changes made in the engine after 1814 
—introduction of high-pressure steam and 
Trevithick’s boilers 49 
65. Trevithick’s first proposition (1806) 
for the use of high-pressure steam in the 
Boulton and Watt engine .... ib. 
66. First Cornish engine—erected by Tre 
vithick in 1812 . . . . .51 
67. Woolf’s application of high-pressure 
steam to Hornblower’s double-cylinder en 
gine ....... 52 
68. Woolf’s erroneous notions respecting 
the nature and properties of steam . . 54 
69. First engines erected by Woolf in 
Cornwall, 1814 to 1816 . . . .55 
70. Excellence of manufacture of Woolf’s 
engines ...... - 56 
71. General introduction of Trevithick’s 
adaptation of the single-cylinder engine, and 
gradual disuse of the double-cylinder, 1816 
to 1821 ....... ib. 
72. Trevithick’s ‘ pole engine ’ . . 57 
73. Converted into an expanding engine 
by Messrs. Sims and Son . . . .58 
74. Changes made in the boilers of the 
Cornish engines—experiments, 1800 to 1814 59 
75. Trevithick’s proposition to substitute 
his locomotive boiler for the common one, 
1806 60 
76. More successful application of Trevi 
thick’s boiler, when high-pressure steam was 
used in the engines, 1816 . . . . 61 
77. Woolf’s tubular boilers—his subse 
quent adoption of Trevithick’s boiler . . ib. 
78. Duty, 1814 to 1821 . . . ib. 
79. First trial to prove the correctness of 
the reports, 1815 . . . . .62 
80. Nature of the alterations made in the 
Cornish engine since 1821 . . . ib. 
81. Promise of general improvement, 1822 
—Captain Grose’s improvements in clothing, 
&c., 1825—application to Wheal Towan en 
gine, 1827 . . . • • .63 
82. Adaptation of Grose’s improvements 
to Woolf’s engine at Consolidated Mines, 
1827—trial of this engine .... ib. 
83. Further improvement of Wheal Towan 
engine, 1828 — trial of its duty—general 
adoption of Grose’s improvements throughout 
the county, and consequent better performance 
of the engine . . . . . .65 
84. Trial oftheFowey Consols engine, 1834 ib. 
85. Number of engines at work in the 
county in 1834, and their dimensions . . 68 
86. Improvement since 1835 . . . ib. 
87. Taylor’s engine at the United Mines 
erected in 1840 by Hocking and Loam—its 
high duty . . . • • . ib.