FOOTNOTES:

[1] In the _Encyclopaedia Britannica_, article "Telescope," and in
Grant's _Physical Astronomy_, good reasons are given for awarding the
honour to Lipperhey.

[2] Will the indulgent reader excuse an anecdote which may encourage
some workers who may have found their mathematics defective through
want of use? James Gregory's nephew David had a heap of MS. notes by
Newton. These descended to a Miss Gregory, of Edinburgh, who handed
them to the present writer, when an undergraduate at Cambridge, to
examine. After perusal, he lent them to his kindest of friends,
J. C. Adams (the discoverer of Neptune), for his opinion. Adams's
final verdict was: "I fear they are of no value. It is pretty evident
that, when he wrote these notes, _Newton's mathematics were a little
rusty_."

[3] _R. S. Phil. Trans_.

[4] The experiment had been made before by one who did not understand
its meaning;. But Sir George G. Stokes had already given verbally the
true explanation of Frauenhofer lines.

[5] _Abh. d. Kon. Bohm. d. Wiss_., Bd. ii., 1841-42, p. 467. See
also Fizeau in the _Ann. de Chem. et de Phys_., 1870, p. 211.

[6] _R. S. Phil. Trans_., 1868.