Page:The humbugs of the world - An account of humbugs, delusions, impositions, quackeries, deceits and deceivers generally, in all ages (IA humbugsworld00barnrich).djvu/272

 and consequently to the navigation of the world. This transit was not calculated to occur before the 7th of November, 1835 (the year in which the hoax was printed;) but Sir John Herschel set out nearly a year in advance, for the purpose of thoroughly testing a new and stupendous telescope devised by himself under this peculiar inspiration, and infinitely surpassing anything of the kind ever before attempted by mortal man. It has been discovered by previous astronomers and among others, by Herschel’s illustrious father, that the sidereal object becomes dim in proportion as it is magnified, and that, beyond a certain limit, the magnifying power is consequently rendered almost useless. Thus, an impassable barrier seemed to lie in the way of future close observation, unless some means could be devised to illuminate the object to the eye. By intense research and the application of all recent improvements in optics, Sir John had succeeded in securing a beautiful and perfectly lighted image of the moon with a magnifying power that increased its apparent size in the heavens six thousand times. Dividing the distance of the moon from the earth, viz.: 240,000 miles, by six thousand, we we have forty miles as the distance at which she would then seem to be seen; and as the elder Herschel, with a magnifying power, only one thousand, had calculated that he could distinguish an object on the moon’s surface not more than 122 yards in diameter, it was clear that his son, with six times the power, could see an object there only twenty-two yards in diameter. But, for any further advance in power and light, the way seemed insuperably closed until a profound conversation