12 farmers' bulletin 603. 



To show the maimer of usiug Tiible 2, the same example may be taken as 

 served to illustrate Table 1, namely, a l.SOO-gallon vat that contains 1,050 

 gallons of bath analyzing 0.14 per cent actual arsenious oxid. which is to be 

 brought to the full water line with standard low-strength bath. Suppose 

 that low-strength boiled arsenic stock is to be employed. From Table 2 it 

 will be found that each 100 gallons of 0.14 i>er cent bath requires 1.36 gallons 

 of low-strength boiled arsenic stock to bring it to the right strength, so for 

 1,050 gallons there is needed 10* X 1.36=14.28 gallons of stock, which would 

 bring the whole volume to 1,050+14=1,064 gallons of proper strength bath. 

 There is then left 1,500—1,064=436 gallons of regular low-strength bath, 

 which must also be introduced to fill the vat, for which there is, of course, 

 needed 464-h20'=23.2 gallons of boiled arsenic stock. Now, 14.28+23.2=37.48, 

 or practically, 37^ gallons of boiled arsenic stock altogether. Therefore water 

 will be run into the vat, about 6 quarts of tar stock being added during the 

 process as called for by the volume of fresh liquid introduce<l, finally leaving 

 just enough room below the full water line for 37i gallons of low-strength 

 boiled arsenic stock which is carefully measured in. 



It appears not worth while to give a table for reducing baths if 

 they are found by analysis to be too strong. This event but seldom 

 occurs, and if it does the amount of water to be added may be easily 

 calculated. If, for example, a bath analyzes 0.25 per cent actual 

 arsenious oxid and is to be reduced to 0.19 per cent, then each 100 

 gallons should be diluted to make 100Xfl=131^ gallons — that is, 

 31^ gallons of water must be added to each 100 gallons of bath in 

 the vat. 



OBTAINING THE CAPACITY OF A VAT. 



To obtain the capacity of a dipping vat the following measure- 

 ments must be taken: (1) Length of the bottom; (2) width of the 

 bottom at its middle point; (3) length of water line; (4) width of 

 water line at its middle point; (5) vertical depth of dip at middle 

 of bottom — that is, at the same point where measurement No. 2 was 

 taken. For future reference it is Avell to mark this point on the side 

 of the vat. The measurements should be. carried to the nearest inch 

 for length, to the nearest half inch for depth, and to the nearest 

 quarter inch for width. 



The measurements taken in feet and inches are now to be reduced 

 to feet and decimals of feet through Table 3. 



1 See page 8. 



