Length of the Metre, he. 215 



chair. The fecal matter, after being thus neutralifed, is an 

 excellent manure for laud. 



LENGTH OF THE METRE. 



From the Journal de Phyfique we learn, that the report 

 which has been made of the length of the metre at Paris by 

 the learned men employed in determining the length of a 

 degree of the meridian, has been fixed at 3 feet 11 lines 

 and 1,296 of a line. On this bafis all the other meafures 

 are to be formed. We fliall give-hereafter a more particular 

 account of this operation, which leads to fome changes in 

 the refults before given by approximation. 



TRANSIT OF MERCURY. 



" I waited with impatience for the paflage of Mercury 

 over the fan's dhk in his defcending node. It had never 

 been completely obfcrved in that pofition, and there will not 

 be another for thirty-three years. I had the pleafure of ob- 

 ferving Mercury enter the fun's difk, like a fmall round 

 black fpot, on the i8th of Floreal (May 7th) in the morn- 

 ing, at the very moment pointed out in my new tables. The 

 principles on which they are founded I have explained in 

 the firll memoir read at the firft meeting of the firft clafs 

 of the Inftitute immediately after its eftablifliment. This 

 is the more fatisfaftory, as, in the calculations for the tranfit 

 of the 4th May 1780, there were forty minutes variation from 

 the beft tables of Mercury. Lalande." 



PREPARATION OF BRUNSWICK GREEN. 



Kafleleyn has lately publiflied the following method of 

 preparing this colour, which is much ufed on the Continent 

 for oil painting, and in the maniifafturing of printed paper. 

 Shavings of copper arc put into a clofe veflel, and befprink- 

 Icd with a folution of the muriat of ammonia. The metal 

 firft unites with the muriatic acid, and is dilfolved, and is 

 in its turn precipitated by the difengagcd ammonia, to 

 which it now joins itfelf. The precipitate is then wafiicd 

 V 4 and 



