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Design Control Plan and stages from Idea to the test phase.

It consists of a bulb containing mercury attached to a glass tube of narrow diameter, the volume of mercury in the tube is much less than the volume in the bulb. The volume of mercury changes slightly with temperature, the small change in volume drives the narrow mercury column a relatively long way up the tube.
In order to calibrate the thermometer, the bulb is made to reach thermal equilibrium with a temperature standard such as an ice/water mixture, and then with another standard such as water/vapour, and the tube is divided into regular intervals between the fixed points. In principle, thermometers made of different material might be expected to give different intermediate readings due to different expansion properties.
Mercury thermometers can be used to determine body, liquid, and vapour temperature. Mercury thermometers are used in households, laboratory experiments, and industrial applications.

Stethoscope, a medical instrument used in listening to sounds produced within the body, chiefly in the heart or lungs. It was invented by the French physician R.T.H. Laënnec, who in 1819 described the use of a perforated wooden cylinder to transmit sounds from the patient's chest to the physician's ear.
Laennec invented the stethoscope because he was not comfortable placing his ear directly onto a woman's chest to listen to her heart.

Alexander Fleming accidentally discovered penicillin. Upon returning from a holiday in Suffolk in 1928, he noticed that a fungus, Penicillium notatum, had contaminated a culture plate of Staphylococcus bacteria he had accidentally left uncovered. The fungus had created bacteria-free zones wherever it grew on the plate. Fleming isolated and grew the mould in pure culture. He found that P. notatum proved extremely effective even at very low concentrations, preventing Staphylococcus growth even when diluted 800 times, and was less toxic than the disinfectants used at the time.
After early trials in treating human wounds, collaborations with British pharmaceutical companies ensured that the mass production of penicillin was possible.
Scientists in Oxford were instrumental in developing the mass production process, and Howard Florey and Ernst Chain shared the 1945 Nobel Prize in Medicine with Alexander Fleming for their role in creating the first mass-produced antibiotic.

Syringes were invented long before hypodermic needles. Pascal’s experimental work in hydraulics stimulated an Egyptian, Ammar bin Ali al-Mawsili to use glass tubes to apply suction for cataract extraction from about 900 CE. Christopher Wren (better known as an architect than for his medical training), used a ‘cut-down’ technique to intravenously inject dogs with poppy sap through goose quill canulae. By 1660 Drs Major and Esholttz used this method on humans with similar fatal results due to ignorance of suitable dosage and the need for sterilizing utensils and the infusion. The disastrous consequences of these experiments delayed the use of injections for 200 years. The first hypodermic needle was probably made by Francis Rynd in Dublin in 1844, but it seems that Alexander Wood in Edinburgh combined a functional syringe with a hypodermic needle in the same year, to inject morphine into humans and probably should be credited with inventing the technique. The basic design has remained unchanged though interchangeable parts and the use of plastic resulted in the almost universal use of disposable syringes and needles since the mid-1950s.