Si Oil the Cutoptrical and Dioptrical 



and " glasse," contain nothing to prevent us from apply- 

 ing them to cither kind of " classe ;" and our extracts from 

 AL^at show that distant objects may be viewed advantageously 

 with both. 



21. From the whole of what has been stated, in my fovir 

 letters, I may now venture to draw a few of the many in- 

 ferences, which cannot fail to force themselves on the mind 

 of the intelligent reader ; but which, in order to avoid all 

 dogmatism, I shall express in the form of queries. 



22. Preparatory, however, to my first query, I must ob- 

 serve, that the cele!:)rated Dr. Zach, of Saxe-Gotha, in exa- 

 mining, as he did in J 784, the unprinted papers of our 

 great Harriot, found that his observations on Jupiter's sa- 

 tellites extended from January iGth, 1610, to February 26th, 

 j612. The renowned G«///6'o di:*covercd those secondary 

 planets on the 7th of January 1610; " so that," says jDr, 

 Zach, " it is not improbable that Harriot was likewise a 

 first discoverer of these attendants of Jupiter." — " It ap^ 

 pears that Harriot had telescopes with magnifvinsc powers 

 of 10, 20, and 30 times." — " And it is very irkely that 

 Hairioi, who lived with so generous^a patron as The Earl 

 cfNorthumberland, had got the new invention of telescopes 

 in Holland much sooner in England than they could reach 

 Galileo, who, at that lime, lived at Venice."- — Now, Har- 

 riot was born in 1560, and died in 1621. The Pantome- 

 tria appears to have been first printed in 1571 *, and a se- 

 cond time in 1591 ; and the Stratioficns first in 1579, and 

 again in 1590. These two interesting books were the joint 

 M'orks of Leonard Digges and his son Thomas Digges, 

 the former of whom died about 1574, and the latter in 

 1595, when Harriot was 3b years of age. Dee's Preface 

 to Euclid was first printed in 1570, and its author lived till 

 1608, when Harriot was in his 45th year. These three 

 performances, therefore, which, as we have seen, (Lett. ii. 



* Here a friend obligingly sent me the first edition of the Pantomelriny 

 •' imprinted at London anno 1571," when 77w. D'igges, esq. the editor, 

 and partly the author, says he was 2; years of aiic. Thus both editions 

 of that work are before me; the first a small 410. (1571), .-md the se- 

 cond a small icl. (1591) apparently much augmented. But I cannot 

 compaie th^m now. — The note at § 2. of my second letter should be read 

 fhusj The P,w/w/.v/;7j< was be^;un by Lwwm/ D/j'^«, and finished by 

 his son I'boiiiHH Di£gfs, The first of the three books of the Siralioticof, 

 WMS begun and almost finished by the father, and the two others wholly 

 written bv the son. See the title of the first ediiiv)n of the Pantomttria.,, 

 and the Dodioation of both editions; also the Pref.ice 10 the Stratioiicos, 

 arid thv Li^t of Ttc D;^^r.''s worksj jst the end of it's Contents. 



§3 



