41. The instruments are : 22-inch reflecting telescope . 42. On 13 March 1781, amateur astronomer William Herschel spotted a new planet with his powerful reflecting telescope . 43. Towards the end of the 19th century very large silver on glass mirror reflecting telescopes were built. 44. But reflecting telescopes had larger problems. 45. Newton also developed the reflecting telescope . 46. The difficulties with the impractical metal mirrors of reflecting telescopes led to the construction of large refracting telescopes. 47. The model was based on observations made by Blunt with his reflecting telescope from his home in Shrewsbury. 48. A third form of reflecting telescope , the " Cassegrain reflector " was devised in 1672 by Laurent Cassegrain. 49. Sagredo also discussed with Galileo the possibility of a telescope using a mirror ( a reflecting telescope ). 50. Subaru is a Ritchey-Chretien reflecting telescope .
