Object of the Month: December 2019

Pálava Ingha II Electric Blanket, Model TH 60, OPP Mikulov, 1969. NML Medical Museum Collection, P 156.

Object of the Month: December 2019

Pálava Ingha II Electric Blanket, 1960s

The winter season asks for a source of warmth. In 2018, these pages showed an 18 century hot water bottle: this winter we looked for a more recent item to heat the bed and the body, an object that testifies to the growing role of electric power in medicine and everyday life during the last 100 years.

Electric blankets began to replace hot water bottles in the 1920s. Looking for the inventor, one often comes across the name of Sidney I. Russell, an American physicians who supposedly devised the blanket in 1912 for heating TBC patients in „fresh air therapy“, lying outside in wintertime. The first patents for heating pads and therapeutic electric blankets appear, however, in the 1890s. Samuel Blumer (1881-1953) began producing them in the Swiss town of Schwanden in 1903. Before World War I, the Berlin-based Allgemeine Elektricitäts-Gesellschaft (Emil Rathenau, 1908) or Milliwatt GmbH (Richard Heilbrun, 1912) made their own electric blankets as well. The Berlin Siemens-Schuckert company introduced its blankets at the International Pharmaceutic Exhibition in Vienna in 1913. In Britain, World War I veterans started the Thermega Corporation, which made blankets for medical use since 1928.

In the 1920s, more and more households on both sides of the Atlantic had access to electricity. Electric appliance merchants found new outlets for their products in kitchens, bedrooms and living rooms. Along with electric lighting, irons, vacuum cleaners, toasters or blenders, electric blankets entered the home, saving both energy and investment. In the 1930s, many Czechoslovak homes were equipped with such devices as well. Both electricity and electric tools became available in the US sooner than in Europe: that may be one reason why the electric blanket inventor was assumed to have been American.

Electric blankets found their place in bedrooms, but they did not disappear from doctor’s offices and hospitals. As well as in the home, they provided patients primarily comfort, not only during fresh-air treatment of tuberculosis. The blanket served to relief muscle and stomach pains, in physical therapy of sciatica or menstrual cramps. It became an essential instrument in treating prematurely born infants. First infant incubators appeared in Paris in 1880, but the acceptance and spread of Étienne Stéphane Tarnier’s (1828-1897) invention was slow and the machines were expensive and inaccessible to most children and birth attendants in any case. A midwife would surround the baby wrapped in cotton wadding and diapers with hot water bottles or electric blankets. Before and during World War II, physicians in America and elsewhere experimented with electric blankets in hyperthermic treatment of gonorrhea as well. The advent of antibiotics limited the scope of physical therapy in treating infectious diseases.

The principal element of an electric blanket is an insulated heating element (a high resistance wire), coiled around an insulator (a ceramic or asbestos rod) and weaved into fabric. Electric current passes through the wire, heats it and warms the blanket, wrapped in firm fabric and often coated with washable sheet. A bimetal thermostat limits the rise of temperature. If the latter passes a threshold the bimetal strip bends, breaking the contact and interrupting the power supply; a fall in temperature straightens the strip and connects the circuit. The power input of the blanket can be controlled manually as well.

In pre-war Czechoslovakia, electric blankets were produced by several factories, including Českomoravská-Kolben-Daněk (ČKD, Electro-Praga), the Brothers Čižek Company (Chirana), the Elektromotor Svet in Brno or Arnold Löwit’s East-Bohemian Cable Company (Východočeská továrna na káble) in Vrchlabí (Hohenelbe). The construction principle of the blanket is, however, relatively simple and if component parts (for temperature regulation) were available, the device could be made by small factories and workshops. Since 1933, the security of blankets was attested by Czechoslovak Electronics Association: the ESČ logo continued to be used after the war and ensured that the blanket will not overheat, inflicting burns or causing fire.

Pálava Ingha II Electric Blanket, Model TH 62, OPP Mikulov, 1960s. NML Medical Museum Collection, P 157/1.

If one purchased an electric blanket in Czechoslovakia after 1945, it probably came from Mikulov. Since the mid-1920s, electric blankets were sold by Max Fehl’s (1868-1943) electrical hardware store and workshop on the Brünner Street No. 8. In the 1930s and during the war, they were sold by the factory of agricultural and electric machines, owned by Hermann Hage (1882-1947). The factory was confiscated after the liberation and in the first post-war years continued production under national administration. Nationalization of trades in 1953 led to the creation of the District Industrial Company (Okresní průmyslový podnik) in Mikulov, which included, together with other small factories and shops, the Elektrovýroba Mikulov (Mikulov Electric Works), known for its electric blankets until late 1980s. (In 1960s, the district seat and the company headquarters moved to Břeclav, but the „blanket shop“ (poduškárna) remained in Mikulov.) In 1965, the factory underwent reconstruction, increased production by half and introduced several new, larger models. Some sources name the Mikulov factory the sole producer of electric blankets in the country: within the Eastern Bloc, the devices were made by several companies in the GDR as well. (At least during a part of the period, however, the nationalized Electro-Praga company made electric blankets in its factory in Miletice. ) The blankets were sold, first, as „Lidová poduška Ingha“ (Ingha People’s Blanket), the obscure name later supplemented with „Palava“ after the natural reserve near in the Mikulov area known for its warm climate.

Mikulov blankets remained on sale until the 1980s, intended as the high point of Christmas season consumer goods offer. In 1987, the Household Trade Fair in Pilsen offered new Ingha III, MIKI (70x 140 cm in size) and AL 1 blankets. Since the 1990s, however, the electric blankets sold in the country have come from abroad. The conclusion of the Czechoslovak blanket story remains open: we hope that with the help of our readers, we will be able to draw it to a close.