Cadwallader C olden with Peter Collinson. Src. 



117 



Dr. Colden to Mr- Collinson. 



May, 1742. 



Dear Sir — I never received any thing with more pleasure 

 than yours of the 7th of March last ; when I perceived by it 

 that I had gained so great a share of your friendship, and that 

 by such means as I had reason to fear might have deterred you 

 from continuing any further correspondence by the trouble it has 

 given you ; and on a subject which proves fruitless, any other- 

 wise than to show how careful a man should be not to be fond 

 of any notions he conceives, or any subject which he does not 

 perfectly understand, and how necessary and useful it is to con- 

 sult those who are skillful. Mr. Graham in three lines, (master- 

 like in mechanics,) not only shows that my notions cannot 

 be reduced to practice, which I only before suspected, but that 



i 



they are likewise faulty in theory in that respect. Pray, sir, re- 

 turn my most humble thanks to him. I can have no hopes of 

 making him any return ; otherwise I should with a great deal of 

 cheerfulness offer my service to him in this country. However, 

 I still so far continue my opinion of the difficulties of making 

 small instruments, especially if they be in any manner com- 

 pounded, and likewise of the difficulty to observe with them to 

 a sufficient accuracy, that I cannot as yet entertain a sufficient 

 esteem of Mr. Sisson's instrument, because of the difficulty of 

 discovering the errors and correcting them, when an entire circle 

 is not used, otherwise than by a long series of observations made 

 with the greatest accuracy. 



Last winter I employed the greatest part of my leisure time in 

 revising the first part of my History of the Five Nations, and in 

 putting into some order the materials which I had collected about 

 the year 1725 for the continuing of it } and I left so much of it 

 as I could then get copied with Mr. Alexander, in March last, to 

 be sent to you by a ship which proposed to sail for London soon 

 after that time ; and since that, I have got the remaining part of 

 it copied, which I now send to him to be forwarded to you. I 

 am truly ashamed that I could not have it copied in a better hand, 

 but in the situation I am in I could not help it. My chief view in 

 that work, I may truly say, is to do you a pleasure. However, if 

 you think it may be useful to the public, you have my full con- 

 sent to publish it in what manner you think fit ; though I have 

 no great fondness to appear as an author, while I am sensible 



