## The Works of John Playfair ...: With a Memoir of the Author ...A. Constable & Company, 1822 |

### From inside the book

Results 1-5 of 24

Page 71

...

...

**perpendicular**height . I must , however , observe , that , on verifying these obser- vations , I have found the rate of the decrease of temperature a little slower than this , and very nearly a degree for 250 feet . This seems to hold ... Page 79

...

...

**perpendicular**cliff . Here , there- fore , the immediate contact of the two rocks is not only visible , but is curiously dissected and laid open by the action of the waves . The rugged tops of the schistus are seen penetrating into the ... Page 153

...

...

**perpendicular**to the surface of the fluid ; it makes an angle with it , de- pending on the aberration , and therefore in some cases less by 20 " than a right angle . On this ac- count , the effect is not produced which Boscovich's ... Page 191

...

...

**perpendicular**to three lines which meet ( at least nearly ) in one point , the centre of the earth . It is called the spherical excess ; and it was in this survey that there came , for the first time , to be any question concerning the ... Page 195

...

...

**perpendicular**from the tower of Dunkirk on the meridian of Greenwich is found to be 547058 feet ; from which , subtracting 9080 feet , the distance of Dunkirk east of the meridian of Paris , we have the**perpendicular**let fall from ...### Common terms and phrases

accuracy accurate afford ancient angles appear arch ascertained astronomical Board of Longitude bodies calculation cause circumstances computation considerable considered deduced degree Delambre determined discoveries distance Dr Black Dr Hutton Dr Simson Dr Stewart Dunkirk earth Edinburgh effect employed England equal equator error experiments extremely fathoms force France French geometer geometry give given gravity heat inequalities instrument investigation irregularities Jupiter known Laplace latitude length less longitude mathematical mathematicians matter means measured ment mentioned meridian method mixed mathematics moon moon's motion mountain Mudge nature nearly never Newton object observations orbit pendulum perpendicular philosophers planets Porisms principle probably problem produced Punnae quantity remark repeating circle revolution Robison Royal schistus seems side spherical excess stations supposed surface theodolite theorem theory thing tion toises trigono trigonometrical survey truth University of Edinburgh vibrations whole zenith

### Popular passages

Page 81 - The mind seemed to grow giddy by looking so far into the abyss of time ; and while we listened with, earnestness and admiration to the philosopher who was now unfolding to us the order and series of these wonderful events, we became sensible how much farther reason may sometimes go than imagination can venture to follow.

Page 335 - ... the three angles of a triangle are together equal to two right angles, although it is not known to all.

Page 309 - ... that the mean longitude of the first satellite, minus three times that of the second, plus twice that of the third, is always equal to two right angles.

Page 125 - The boast of heraldry, the pomp of power, And all that beauty, all that wealth e'er gave, Await alike the inevitable hour — The paths of glory lead but to the grave.

Page 325 - In one of these, where the dictates of Aristotle are still listened to as infallible decrees, and where the infancy of science is mistaken for its maturity, the mathematical sciences have never flourished ; and the scholar has no means of advancing beyond the mere elements of geometry.

Page 522 - An account of experiments for determining the length of the pendulum vibrating seconds in the latitude of London.

Page 55 - It is unreasonable, indeed, to suppose that such marks should any where exist. The Author of nature has not given laws to the universe, which, like the institutions of men, carry in themselves the elements of their own destruction ; he has not permitted in his works any symptom of infancy or of old age, or any sign by which we may estimate either their future or their past duration.

Page 56 - The Author of nature has not given laws to the universe, which, like the institutions of men, carry in themselves the elements of their own destruction. He has not permitted, in his works, any symptom of infancy or of old age, or any sign by which we may estimate either their future or their past duration. He may put an end, as he no doubt gave a beginning, to the present system, at some determinate period; but we may safely conclude, that this great catastrophe will not be brought about by any of...

Page 301 - Between the laws by which the tides diminish from their maximum at the full and change, to their minimum at the first and third quarters, and by which they increase again from the minimum to the maximum, as deduced from the observations at Brest, and as determined by the theory of gravitation, there is an exact coincidence. 2. According to theory, the height of the tides...

Page 439 - ... most general rule that we are enabled to give admits of many exceptions. The violation of the order of events among the phenomena of the former class, the suspension of gravity, for example, the deviation of any of the stars from their places or their courses in the heavens, &c., — these are facts of which the improbability is so strong that no testimony can prevail against it.