Electrical measurement of a physical quantity

Claim 1

AN ELECTRICAL MEASURING INSTRUMENT FOR MEASURING A PHYSICAL QUANTITY COMPRISING A BRIDGE CIRCUIT, SAID BRIDGE CIRCUIT HAVING ITS RATIO ARMS IN THE POTENTIAL BALANCE PART OF THE BRIDGE COMPRISING THE SECONDARIES OF A TRANSFORMER, AND SAID BRIDGE CIRCUIT HAVING AT LEAST TWO MEASURING ARMS, ONE OF SAID MEASURING ARMS COMPRISING AT LEAST ONE NON-INDUCTIVELY WOUND RESISTANCE ELEMENT RESPONSIVE TO SAID PHYSICAL QUANTITY TO BE MEASURED, ANOTHER OF SAID MEASURING ARMS COMPRISING AT LEAST ONE NON-INDUCTIVELY WOUND RESISTANCE ELEMENT NON-RESPONSIVE TO SAID PHYSICAL QUANTITY, AND SAID BRIDGE CIRCUIT HAVING AT LEAST ONE OF THE NON-INDUCTIVELY WOUND RESISTANCE ELEMENTS OF AT LEAST ONE OF SAID MEASURING ARMS LOCATED AT A POINT ELECTRICALLY REMOTE FROM THE POTENTIAL BALANCE PART, SAID REMOTE ELEMENT BEING SUFFICIENTLY REMOTE FOR THE IMPEDANCE OF A LEAD CARRYING THE ENERGISING CURRENT OF THE BRIDGE AND CONNECTING THE REMOTE ELEMENT TO THE POTENTIAL BALANCE PART TO CAUSE A SIGNIFICANT VOLTAGE DROP COMPARED WITH THAT VOLTAGE DROP APPEARING ACROSS SAID REMOTE ELEMENT, AN A.C. VOLTAGE SOURCE COUPLED TO AT LEAST THE SAID REMOTE ELEMENT THROUGH A LEAD WHICH IS INDEPENDENT OF THE LEADS FEEDING THE POTENTIAL DROP ACROSS THE REMOTE ELEMENT TO THE POTENTIAL BALANCE PART OF THE BRIDGE, AND MEANS FOR NEUTRALIZING THE EFFECT ON THE POTENTIAL BALANCE PART OF THE BRIDGE OF THE VOLTAGE DROP DUE TO THE ENERGISING CURRENT FLOWING IN THE ELECTRICALLY LONG LEAD TO THE REMOTE ELEMENT.