All day, all night, all week . . . CONTINUOUS FLOW TITRATOR The HACH Model 1407 makes con­tinuous titration easy. Here is the ideal instrument for alkalinity, hard­ness, acid-base, and most titrations where there is a color change at the end-point.

A sample stream, a colorimetric indicator stream and a t i trat ing reagent stream are blended and pass through the analyzer continuously. The rate of flow of the t i trat ing rea­gent is adjusted automatically so that a color change end-point is main­tained in the stream mixture. The concentration of the substance being determined is indicated on a 16 inch graduated scale. A recorder may be added when a permanent record and/or alarm or control functions are desired.

Maintenance is kept to a minimum. Monthly reagent refil l, weekly colori­meter adjustment and periodic lubri­cation will insure long trouble-free operation.

The HACH Model 1407 is shipped set-up for a specified titration with all necessary fitt ings, month supply of reagents, hoses, gray steel case and operating instructions. Base price $1,695.

Write or call for complete information today.

HACH CHEMICAL COMPANY Box 907 · Ames, Iowa

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