124 THE HISTORY AND DEVELOPMENT OF THE MICROSCOPE 



Florence on September 23, 1624, more than three months after his 

 departure from Rome : 



1 1 senrl your Excellency an occhialino, by which to see close the 

 smallest things, which I hope may give you no small pleasure and 

 entertainment, as it does me. I have been long in sending it. because 

 I could not perfect it before, having experienced some difficulty in 

 finding the way of cutting the glasses perfectly. The object must 

 be placed on the movable circle which is at the base, and moved to 

 see it all, for that which one sees at one look is but a small part. 

 And because the distance between the lens and the object must In- 

 most exact, in looking at objects which have relief one must be able 

 to move the glass nearer or further, according as one is looking at 

 this or that part ; therefore the little tube is made movable on its stand 

 or guide, as we may wish to call it. It must also be used in very 

 bright, clear weather, or even in the sun itself, remembering that the 

 object must be sufficiently illuminated. I have contemplated very 

 many animals with infinite admiration, amongst which the flea is 

 most horrible, the gnat and the moth the most beautiful ; and it was 

 with great satisfaction that I have seen how flies and other little 

 animals manage to walk sticking to the glass and even feet upward*. 

 But your Excellency will have the opportunity of observing thousands 

 and thousands of other details of the most curious kind, of which I 

 beg you to give me account. In fact, one may contemplate endlessly 

 the greatness of Nature, and how subtilely she works, and with what 

 unspeakable diligence. P.S. The little tube is in two pieces, and 

 you may lengthen it or shorten it at pleasure.' 



It would be very strange, knowing Galileo's character, that in 

 1624, and after the attacks made on him for having perhaps a little 

 too much allowed the Dutch telescope to be considered his invention, 

 he should have been induced to imitate Drebbel's glass with the two 

 convex lenses, and have wished to make them pass as his own invention, 

 whilst he had always used, and continued to use to the end of his days, 

 telescopes with a convex and a concave lens without showing that 

 he had read or in the least appreciated the proposal made by Kepler, 

 ever since 1611, to use two convex glasses in order to have telescopes 

 with a large field and more powerful and convenient. 



In any case it is impossible to form a decided opinion on such a 

 matter, the data failing ; but the very fact that from 1624 onwards 

 Galileo thought no more of the occhialino (probably because he found 

 it less powerful and less useful than the occhiale of Drebbel), as he 

 had not occupied himself with it or had scarcely remembered it from 

 the year 1610 to 1624, seems sufficient to show that the occhialino, 

 like the microscope of 1610, was a small Dutch telescope with two 

 lenses, one convex and one concave, and not a reduced Kepleriari 

 telescope like that invented by Drebbel in 1621. 



The name of microscope, like that of telescope, originated with 

 the Academy of the Lincei, and it was Giovanni Faber who invented 

 it, as shown by a letter of his to Cesi, written April 13, 1625, and 

 which is amongst the Lincei letters in the possession of D. B. Bon- 

 compagni. Here is the passage in Faber's letter : 



' I only wish to say this more to your Excellency, that is, that 



