Sulphuric Acid-manufacture. 



35 



the percentages of sulphuric acid, corresponding to the lines in 

 Diagram 11 a. 



The numbers " per cent." &c. represent the percentage of 

 acid at 15 feet from bottom of chamber. 



The numbers "8i per cent." &c. represent the percentage of 

 acid at 3 feet from bottom of chamber. 



In Diagram Ha, as in Diagram la, the top figures denote 

 the length of the chamber divided into spaces of 10 feet each, 

 whilst the side figures denote the percentage of acid present. 



The dotted line represents the amount of acid at 3 feet from 

 bottom of chamber. 



The white line represents the amount of acid at 15 feet from 

 bottom of chamber. 



On comparing this with Diagram I a } the similarity is very 

 striking. It is only required to place the white line in Diagram I. 

 on the dotted line in Diagram II., and vice versa. In No. L 

 the greatest amount of sulphurous acid is at the top of the cham- 

 ber, and the smallest amount at the bottom. In No. II. the 

 largest amount of sulphuric acid is at the bottom of the chamber, 

 whilst the smallest amount is at the top. 



Proportional Tables for Diagrams II. 



No. I. At 15 feet height. 



No. II. At 3 feet heigh 



Feet from end of chamber. 



Feet from end of chamber. 



30 =1 



120 V 1-2 

 130 J - 14 



1001 

 120 J - 1 

 140 =1-1 



140 =1-7 

 1001 o 



lioj-^ 



110 1-D2 



laof-M 



90 =1-6 



80 =2-7 



80 =1-8 



40 l-3 



70 J" 6 i 



90 =3-2 



70 =2 



60 =3-3 



40 =2-3 



50 =3-7 



30 =2-5 



10 1-0 

 20 J _u 



10 =2-7 

 20 =2-9 



Nitric a 



Acid, 



The variations in the percentage of nitric acid are not very 

 great, being only between 3 per cent, and 26 per cent., these 

 being the maximum and minimum amounts. It attains its 

 greatest height at 100 and 110 feet from end of chamber, and 

 then sinks very rapidly down to 3 per cent, at 140 feet. 



D2 



