Jimmy helped demonstrate an early version of an electrocardiogram (ECG or EKG), a machine that measures the electrical activity of the heart.
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| A demonstration to the Royal Society by Waller's dog Jimmy (1909) |
Today's EKG machine has come a long way, thanks to many scientists and inventors. The first machine was invented in 1903. It weighed about 600 pounds and required patients to put their limbs into buckets of salt water.
The first practical EKG machine with surface electrodes was created by Augustus Desiré Waller. He lectured on it in Europe and America, often using his pet bulldog Jimmy in his demonstrations. The Times newspaper reported that the demonstration had caused debate in parliament over whether the Cruelty to Animals Act had been violated. The Secretary of State replied as follows: I understand the dog stood for some time in water to which sodium chloride had been added or in other words a little common salt. If my honourable friend has ever paddled in the sea he will understand the sensation. (Laughter) The dog — a finely developed bulldog — was neither tied nor muzzled. He wore a leather collar ornamented with brass studs. Had the experiment been painful the pain would no doubt have been immediately felt by those nearest the dog. (Laughter)
Today's EKG machines weigh just a few pounds and have played a central role in checking for signs of heart disease.
