Indicating and control system responsive to demand

Claim 1

IN A SYSTEM FOR THE TREATMENT WITH CHLORINE OF A MAIN FLOW OF UNCHLORINATED AQUEOUS LIQUID, IN COMBINATION, MEANS COMPRISING A MAIN VESSEL FOR SAID MAIN FLOW, FOR ADVANCING SAID UNCHLORINATED LIQUID ALONG SAID VESSEL IN A PREDETERMINED DIRECTION PAST A FIRST LOCALITY OF THE VESSEL TO A SECOND LOCALITY THEREOF DOWNSTREAM OF THE FIRST LOCALITY, ADJUSTABLE MEANS CONNECTED TO SAID VESSEL AT THE SECOND LOCALITY FOR THERE SUPPLYING CHLORINE TO SAID MAIN FLOW, AND MEANS CONNECTED TO SAID VESSEL AT THE FIRST LOCALITY, FOR DETERMINING IN ADVANCE THE DEMAND OF THE UNCHLORINATED LIQUID FOR TREATMENT WITH CHLORINE TO REACH A DESIRED STANDARD RESULT OF SUCH TREATMENT, SAID DEMANDDETERMINING MEANS COMPRISING CONDUIT MEANS FOR WITHDRAWING A SAMPLE FLOW OF SAID UNCHLORINATED LIQUID, AT A CONTROLLED RATE, FROM SAID VESSEL AT SAID FIRST LOCALITY, ELECTROLYTIC CHLORINE GENERATING MEANS CONNECTED TO SAID CONDUIT MEANS FOR CHLORINATING SAID SAMPLE FLOW AT A RATE GOVERNED BY SUPPLY OF CURRENT TO SAID GENERATING MEANS, ADJUSTABLE CURRENT SUPPLY MEANS HAVING A CIRCUIT EXTENDING TO SAID CHLORINE GENERATING MEANS FOR ENERIZING THE LATTER, MEANS ASSOCIATED WITH THE CONDUIT MEANS DOWNSTREAM OF THE SAMPLE CHLORINATING MEANS FOR TESTING THE SAMPLE FLOW OF LIQUID AFTER CHLORINATION, TO PRODUCE AN ELECTRICAL SIGNAL VARIABLE WITH THE CHLORINE CONTENT OF THE TREATED LIQUID, STANDARD MEANS FOR PRODUCING, INDEPENDENTLY OF THE CHARACTER OF THE LIQUID, A CONSTANT, COMPARABLE ELECTRICAL SIGNAL REPRESENTING THE AFORESAID DESIRED STANDARD RESULT OF CHLORINE TREATMENT, AND CYCLICALLY OPERATING MEANS ELECTRICALLY DIRECTLY RESPONSIVE TO DEPARTURES OF THE FIRST SIGNAL FROM THE SECOND SIGNAL AS REPRESENTING DEPARTURE OF THE CHLORINE CONTENT OF THE TREATED LIQUID FROM THE DESIRED STANDARD RESULT OF TREATMENT, FOR PERIODICALLY ADJUSTING SAID CURRENT SUPPLY MEANS TO CHANGE THE RATE OF CHLORINATION BY THE GENERATING MEANS IN A DIRECTION TO RESTORE THE CHLORINE CONTENT OF THE TREATED LIQUID TO THE DESIRED STANDARD RESULT.