3l6 Dr Robertson mi some Mistalces relating to Dr Bradley's 
had not read Archimedes when he wrote the 8th and 9th ar- 
ticles, as they are so very much inferior to what we have by that 
celebrated mathematician on the subject. 
To these remarks upon die substance of the first ten articles, 
it may be proper to add, that they are destitute of the principal 
particulars requisite in regular mathematical composition. No 
first principles are laid down ; due arrangement is overlooked ; 
and the demonstrations, -often defective, are expressed in a kind 
of algebraical short-hand. In saying this, I by no means in- 
tend to insinuate any thing disrespectful to the memory of Har- 
riot. I offer these observations as reasons for my firm persua- 
sion that he never intended the papers for publication ; and that 
it would be injurious to his reputation to print them. ^ 
The paper De rejlectione corporum rotundorum^ when com-^ 
pared with those already mentioned, may be considered as high- 
ly finished, but to its publication some strong objections may 
be made. Harriot himself states its imperfections, in his letter 
which accompanies this * ; and to these imperfections it may be 
added, that every thing depending upon the composition and re- 
solution of forces is so much better understood, and more clear- 
ly treated, since the great discoveries of Sir Isaac Newton, that it 
would suffer much upon a comparison with modern publica- 
tions. The subject is more fully and elegantly handled in KeilPs 
Introduction to Natural Philosophy, 
Of the other bundle (f papers. — To a great many of these 
papers there is no title, nor do they admit of any specific de- 
scription. They appear to be rough calculations of some parti- 
culars which he wished to ascertain, without any allusion to the 
data with which he set out, or obvious tendency to the object in 
view. Others admit pf classification, and afford abundant proof 
of Harriots zeal in the cause of science, and of his unremitting 
attention to its improvement. 
The first class of this description relates to the spots on the 
sun. From these papers it appears^ that he first began to ob- 
• This was a copy of a letter to his patron the Earl of Northumberland, upon 
the nature of his paper, acknowledging its want of first principles, and its brevity, 
but intimating that he thought his Lordship would comprehend it, notwithstanding 
its defects. 
