Description

Thermometer Mercury Clinical

This mercury clinical thermometer is a device used for measuring body temperature. It is typically made of glass and consists of a long, thin tube called a capillary, a bulb on one end containing the mercury, and a scale on the side.

Components:

• Glass Tube (Capillary): This is a long, thin tube made of glass that is sealed at one end.
• Mercury Bulb: A small bulb located at the bottom of the capillary tube. This bulb contains the mercury metal.
• Scale: A temperature scale is etched along the side of the capillary tube. This scale is usually marked in degrees Celsius (°C) or Fahrenheit (°F).
• Constriction: Some mercury thermometers have a constriction near the base of the bulb. This constriction allows the mercury to pass through easily when the temperature rises but makes it difficult for the mercury to return to the bulb on its own when the temperature falls. This allows for easier reading of the maximum temperature reached.

How it Works:

1. Before Use: The mercury is typically positioned entirely within the bulb due to the constriction (if present). To reuse the thermometer, the user must “shake down” the mercury back into the bulb below the scale.
2. Temperature Measurement: When placed in contact with a body (usually under the tongue, in the armpit, or rectally), the mercury in the bulb expands due to the body heat.
3. Reading the Temperature: The mercury level rises within the capillary tube, and the user can read the temperature at the top of the mercury column on the scale.

Historical Uses:

Mercury clinical thermometers were once the standard tool for measuring body temperature in homes and healthcare settings. They were widely used for decades due to their:

• Accuracy: Mercury thermometers can be very accurate when used correctly.
• Durability: Glass thermometers are relatively robust and can last for many years with proper care.
• Low Cost: They were a relatively inexpensive way to measure body temperature.