Telescope, ^c. ivere first known in England. 249 



enced, or at least regarded as real, by the inhabitants of hot 

 countries, even at considerable distances from the water ? 

 Whether if such heat, instead of being indefinitely diffused, 

 could be united in one spot, a very great effect might not be 

 expected at a very great distance ? Whether Buffon has as- 

 certained the limit, the ne plus ultra, at which combustion 

 can be produced by the reflected solar rays ; and whether, 

 on the contrary, he does not confidently affirm, that, with 

 9 better apparatus, he could have produced the same effect 

 at a proportionably greater distance, as from the nature of 

 the case itself he evidently could ? Whether, if Mauper-^ 

 tuis's idea of an amphitheatre lined with mirrors were re- 

 alized ; or if, as you once suggested, a body of 2000 or 3000 

 men, each furnished with a speculum, were trained to direct 

 the sun's image to a particular spot, bodies might not be 

 inflamed at distances of which at present we have no con- 

 ception? As the Diggeses, both father and son, appear to 

 have enjoyed, at one part at least of their lives, the invalu:^ 

 able privilege of making any costly experiments they thought 

 "proper at the public expense*, whether they may not have 

 possessed an apparatus as much larger than Euffon's, as the 

 eiFect was greater? 



7. Whatever answers your intelligent readers may think 

 due to these queries, not a man of them will doubt that 

 Digges, the father, actually fired gun-powder, a/ iowze^rea^ 

 distance, by n)eans of the reflected rays of the sun ; and if 

 so, lord Napier's first proposal must have been anticipated 

 by many years. 



8. I thought the two foregoing passages from the Pan^ 

 tometria, especially the second, sufficiently wonderful ; but, 

 when I had written thus far, a learned and worthy friend of 

 yours and mine put into -my hand the Stratioticos of 

 Thomas Digges f, printed in London in 1390; at the 339th 

 page of which I find the following astonishing, but, as I 

 hope to prove, not unaccountable passage : 



9. My father, " joyning continual experience" fm the 

 use of artillery) " for many yeares with geometricall de- 

 monstrations, sought, and at last found, and did frame aii 

 instrument, with certaine scales of randons, to perfourme 

 all that Tartalea by his tables promised : as also by reflec- 

 tion of glasses to fire poudcr ai^d discharge ordinance many 



• See Pantometria, p. 171;. 



t In a list of Thomas Diggcs'r, works, at the beginning of the Srrnio- 

 licos, we find that he was the sole author of that piece, and ihat the Pan' 

 tomeiria (second edition) wjis bei^un fcy his father, and augmented and 

 inhhcd by himself. 



miles 



