Circulation Of Blood by William Harvey
William Harvey (1578-1657), and English physician is credited with discovering the mechanism by which blood circulates in mammals, including human race.
He published his discovery in Anatomical exercise concerning the motion of the Heart and of the Blood in Animals, in 1628.
In that work he did not explicitly compare the heart to a pump, although he did so in his lecture and in one small publication.
Harvey’s method by contrasts to some prior work on related questions, were based on direct observation and on dissection of both human and animal cadavers.
His views overthrew those of Galen, the ancient Greek whose views on the question had become accepted dogma. Galen believed that the liver changed food into blood and that blood flowed through the veins to the body, which consumed it.
Harvey showed that the heart operated as a pump , forcing blood through the arteries to the body and that it returned through the veins to the heart in a closed circulation system.
He also demonstrated the cause of the pulse in the expansion of the arteries following contraction of the heart muscles.
He demonstrated that the pumping chamber or right ventricle of the heart sends blood to the lungs, while the left ventricle supplies blood to the rest of the body through the arteries.
Among his other findings was a measurement of the quantity of blood in the body at a particular moment and studies of the part played by the egg in mammalian reproduction.
He also criticized the concept that illness derived from general changes in humors and instead believed in a more modern notion that it resulted from changes in local tissue.
Harvey’s experiments, while contradicting the assumptions of Galen, confirmed the views of several earlier physicians, including the 13th century Arab Ibn-an-Nafis and the Spaniard Miguel Serveto (Michael Servetus) and the Italian Realdo Colombo and Andrea Cesalpino in the mid 16th century.
Each of these doctors had suspected that blood from the veins passed through the heart and thence to the arteries. None, however had explained the whole system as one of circulation, nor had they traced all the components of the system as clearly as did Harvey.
Harvey at first developed a hypothesis of circulation, which he then later confirmed through experimentation, determining the direction of blood flow. Rather than relying on a nebulous force that moved the blood through the body, Harvey showed that motion as resulting from a specific mechanical action.
Like many other discoveries of the Scientific Revolution, those of Harvey derived from careful and structured observation of facts and restating them with clarity.
Circulation Of Blood by William Harvey
William Harvey (1578-1657), and English physician is credited with discovering the mechanism by which blood circulates in mammals, including human race.
He published his discovery in Anatomical exercise concerning the motion of the Heart and of the Blood in Animals, in 1628.
In that work he did not explicitly compare the heart to a pump, although he did so in his lecture and in one small publication.
Harvey’s method by contrasts to some prior work on related questions, were based on direct observation and on dissection of both human and animal cadavers.
His views overthrew those of Galen, the ancient Greek whose views on the question had become accepted dogma. Galen believed that the liver changed food into blood and that blood flowed through the veins to the body, which consumed it.
Harvey showed that the heart operated as a pump , forcing blood through the arteries to the body and that it returned through the veins to the heart in a closed circulation system.
He also demonstrated the cause of the pulse in the expansion of the arteries following contraction of the heart muscles.
He demonstrated that the pumping chamber or right ventricle of the heart sends blood to the lungs, while the left ventricle supplies blood to the rest of the body through the arteries.
Among his other findings was a measurement of the quantity of blood in the body at a particular moment and studies of the part played by the egg in mammalian reproduction.
He also criticized the concept that illness derived from general changes in humors and instead believed in a more modern notion that it resulted from changes in local tissue.
Harvey’s experiments, while contradicting the assumptions of Galen, confirmed the views of several earlier physicians, including the 13th century Arab Ibn-an-Nafis and the Spaniard Miguel Serveto (Michael Servetus) and the Italian Realdo Colombo and Andrea Cesalpino in the mid 16th century.
Each of these doctors had suspected that blood from the veins passed through the heart and thence to the arteries. None, however had explained the whole system as one of circulation, nor had they traced all the components of the system as clearly as did Harvey.
Harvey at first developed a hypothesis of circulation, which he then later confirmed through experimentation, determining the direction of blood flow. Rather than relying on a nebulous force that moved the blood through the body, Harvey showed that motion as resulting from a specific mechanical action.
Like many other discoveries of the Scientific Revolution, those of Harvey derived from careful and structured observation of facts and restating them with clarity.
Circulation Of Blood by William Harvey
