164 Silt held in suspension in the Hooghly. [No. % 



3. As the velocities increase with the depths, there will be as 

 much greater discharge during the freshes. 



Me. Bedeoed. 

 At Jiggerkolly. 



1. Mean level above Zero (of the tide guage, see below) 7 feet 

 1.3 inch. 



2. Velocity per second, in inches at surface, is 62,57 ; at bottom 

 47,747. Mean (as in table) 55,159. 



At Moyapore. 



1 . Mean level above Zero 8 feet 9.4 inches. 



2. Surface velocity in inches 40,42 ; at bottom 28,704. Mean 

 as in table 34,562. 



3. The mean level above Zero is the mean of all the Begisters 

 taken every quarter of an hour on a guage, the Zero of which was 

 on the same absolute level as the Zero of the Tide-guage at the old 

 Kidderpore Docks. 



4. The mean depth is the mean of all the perpendicular co-ordi- 

 nates of the section taken at every 100 feet from the above mean 

 level to the bed of the river. 



5. The velocity at the surface in inches is the mean of the velo- 

 cities taken every quarter of an hour from high water. 



6. The velocity at the bottom is taken from the usual formula 

 tables (De Buat's.) 



7. The fall of the ebb tide between Calcutta and Jiggerkolly 

 was about 6 feet 6 inches in the whole distance, which is about 68 

 geographical miles of 2028 yards each. 



8. The foregoing two sets of observations for the discharge were 

 taken at Jiggerkolly on the 16th March, and at Moyapore on the 

 29th March, 1854. The range of tide at Calcutta on these two dates 

 differed but 3 inches, being so much in excess on the 29th March. 



Memoeandttm. — Mr. Bedford's note giving the discharge in gal- 

 lons, I have assumed that Imperial gallons of 277,274 cubic inches 

 are intended, and have thus allowed 6.34 gallons to the cubic foot 

 in converting his numbers to suit our table. — H. P. 



