Sometimes it's difficult to separate medical electricity from physiological instrumentation. A pacemaker keeps the heart beating properly - but the point is to have sufficient blood pressure and blood flow. Thus, measuring blood pressure (which needs no electricity) is very important as a precursor to possible electro-medical intervention.

The work of E. J. Marey is an excellent example. Marey was a pioneer of the "graphic method", of recording physiological data by machine. There was not much electricity involved; but when the two came together the information gleaned was very significant. Marey studied the physiology of muscles, including the heart; and using electrical stimulation, he was the first to discover the refractory interval. This is a short period of time after the heart beats, during which electrical stimulation will not cause another heartbeat. The existence of this interval was very significant for the early pacemakers, which were not directly synchronized to the heartbeat. The graphic method also is applied today whenever we take an electrocardiogram.

Likewise, Duchenne de Boulogne found that electrical stimulation was an excellent diagnostic tool, letting him tell whether a given paralysis was a disease of the nerves or the muscles. His studies led to the description of Duchenne muscular dystrophy, and to some of the best maps of the stimulus points for the nerves and muscles.

We have many books and devices relating to these two worthies; and there is no sense in being narrowly focused on their electrical researches while ignoring their other interests. Therefore, we have quite a few hemodynamic devices in our collection alongside the purely electrical objects.

N1 recording devices
N1.1 kymographs (drum or endless loop)
N1.2 strip-chart recorders (not drum or endless loop)
N1.3 cameras
N2 sensing devices
N2.1 direct pickup (e.g. myograph)
N2.2 plethysmograph
N2.3 Marey tambour and allied devices
N2.4 thermometric
N2.5 direct electrical pickup
N2.6 sphygmographs
N2.7 stethoscopes
N3 indicating devices
N3.1 direct connection
N3.2 fluid level (e.g. Mosso plethysmograph)
N3.3 pressure (e.g. tambour)
N3.4 electromagnetic
N4 stimulating devices
N4.1 mechanical
N4.2 electrical
N4.3 chemical
N4.4 thermal

Museum Hours: Tuesday - Saturday 10 to 5
Thursdays 10 am to  8pm 
Closed Major Holidays
Library Hours: Monday - Friday 9 to 4:30

Admission: $7 Adults; $5 Students & Seniors; Children 3 and under are FREE!

© The Bakken Updated: April 6, 2007