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AGRICULTURAL ENGINEERING 



should vary with the amount of water which must pass 

 through it. Some engineers use Kutter's formula, given 

 in the chapter on land drainage. To determine the required 

 area of the cross-section of a culvert, a more simple formula 



Fig. 95. Making a concrete culvert. 



has been proposed by Professor A. N. Talbot, of the Uni- 

 versity of Illinois. Professor Talbot states that the formula 

 is to be used as a guide to judgment. It is stated as follows: 



