In Munich, German chemist Max von Pettenkofer (1818-1901) and German physiologist Carl von Voit (1831-1909) measured the carbon dioxide production during labor in the Pettenkofer respiration room. A young worker had to turn a wheel with a 25 kg chain. Because the Pettenkofer room did not allow detection of rapid air changes, these experiments required a long observation period, the subject had to work continuously for nine hours.
According to Scottish William Macewen (1848-1924) of the University of Glasgow, the periosteum had no osteogenic properties. Macewen was a pioneer in modern brain surgery and contributed to the development of bone transplantation, the surgical treatment of hernia and pneumonectomy.
To change the interval between stimulation and sampling, German physiologist Julius Bernstein (1839-1917) used the rheotome of his teacher Emil DuBois-Reymond (1818-1896). The device was called the 'differential rheotome' and the very first ECG was registered with it. Most ECGs came from frog hearts, where the electrodes were placed directly on the heart. Bernstein became known for his explanation about the origin of the 'resting and action potential' of nerves and muscles. In 1902 he developed the 'membrane theory' of electrical potentials in biological cells and tissues, which gave the first practical physico-chemical explanation about bioelectric events. This hypothesis is generally accepted as the first quantitative theory in electrophysiology.
French physiologist, zoologist and politician Paul Bert (1833-1886) introduced the total body plethysmography.
In a closed plethysmography system he performed intense animal experiments. He presented his research to the 'Société de Biologie' under the title 'Changement de pression de l'air dans un poumon pendant les deux temps de l'acte respiratoire' (Changes in air pressure in a lung during the 2 phases of respiration). However, together with the plethysmography he did not do spirometry measurements and no measurements in humans.
The dynamometer developed by Belgian-French instrument maker Louis Mathieu (1817-1879).