PHYSICAL AND MATHEMATICAL SCIENCES. 165

not dwell upon the invention, his thoughts being nowwholly absorbed on the perfection of the telescope, andthe glorious field of astronomical discovery which waslaid open to him.

Being at Venice, his house was thronged with visiters,who came to satisfy themselves of the truth of thewonderful stories they had heard of his invention. Thedoge suggested that a telescope would he an acceptablepresent to the state. Galileo took the hint, and was inreturn confirmed for life in his professorship at Padua,and his stipend doubled. The public curiosity on thesubject was excited to the highest pitch. Sirturi, whohad made one of these instruments, attempting to tryits powers from the top of the tower of St. Mark’s, inVenice, was soon observed by the crowd, who detainedhim for hours to satisfy their curiosity in lookingthrough his telescope. Instruments of an inferior sortwere now made every where, and spread rapidly overEurope ; but the manufacture of the superior kind wasconfined almost solely to Galileo , and those whom heinstructed.

“ The invention of the telescope,” professor Playfairobserves, “ is the work in which (by following uncon-sciously the plan of nature in the formation of the eye)man has come the nearest to the construction of a neworgan of sense.A series of scientific improve-

ments, continued for more than 200 years, has conti-nually added to the perfection of this noble instrument,and has almost entitled science to consider the telescope

as its own production.After the invention of

the telescope, that of the microscope was easy ; and itis to Galileo that we are indebted for this instrument,which discovers an immensity on the one side of manscarcely less wonderful than that which the telescopediscovers on the other. The extension and divisibilityof matter are thus rendered to the natural philosopheralmost as unlimited as the extension and the divisibilityof space are to the geometer.” *

l * Dissertation on the Progress of Science, pp. 248—250. Works, voL lM 3