Boyles Law.
As SCUBA divers we all have to learn a variety of gas laws as part of our dive education. The very first one we are all introduced to (during your Open Water Diver program) is "Boyles Law".
Boyle's Law describes the role of water pressure in the dive environment. It applies and affects many aspects of scuba diving, for example: Ascent - As a diver ascends, water pressure decreases, so Boyle's Law states that the air in his gear and body expand to occupy a greater volume. Remember your instructor telling you to "never hold your breath during ascent"? This is due to the effects of the law on us as divers and is definitely good advice in the prevention of a pressure related injury to the lungs.
What is Boyles Law?
Remember P1V1 = P2V2?
Boyle’s law is a gas law which states that the pressure exerted by a gas (of a given mass, kept at a constant temperature) is inversely proportional to the volume occupied by it. In other words, the pressure and volume of a gas are inversely proportional to each other as long as the temperature and the quantity of gas are kept constant.
Boyle’s law was put forward by the Anglo-Irish chemist Robert Boyle in the year 1662, but who was Robert Boyle? Lets find out a little bit more about him.
Who was Robert Boyle?
Robert Boyle was born January 25, 1627 at Lismore Castle, County Waterford, Ireland. He died December 31, 1691 in London, England and by then was known as an Anglo-Irish natural philosopher and theological writer, a preeminent figure of 17th-century intellectual culture. He was best known as a natural philosopher, particularly in the field of chemistry, but his scientific work covered many areas including hydrostatics, physics, medicine, earth sciences, natural history, and alchemy.
His prolificoutput also included Christian devotional and ethical essays and theological tracts on biblical language, the limits of reason, and the role of the natural philosopher as a Christian. He sponsored many religious missions as well as the translation of the Scriptures into several languages. In 1660 he helped found the Royal Society of London.
Early life and education
Boyle was born into one of the wealthiest families in Britain. He was the 14th child and 7th son of Richard Boyle, the 1st earl of Cork, by his second wife, Catherine, daughter of Sir Geoffrey Fenton, secretary of state for Ireland. At age eight, Boyle began his formal education at Eton College, where his studious nature quickly became apparent. In 1639 he and his brother Francis embarked on a grand tour of the continent together with their tutor Isaac Marcombes.
In 1642, owing to the Irish rebellion, Francis returned home while Robert remained with his tutor in Geneva and pursued further studies. Boyle returned to England in 1644, where he took up residence at his hereditary estate of Stalbridge in Dorset. There he began a literary career writing ethical and devotional tracts, some of which employed stylistic and rhetorical models drawn from French popular literature, especially romance writings.
In 1649 he began investigating nature via scientific experimentation, a process that enthralled him. From 1647 until the mid-1650s, Boyle remained in close contact with a group of natural philosophers and social reformers gathered around the intelligencer Samuel Hartlib. This group, the Hartlib Circle, included several chemists—most notably George Starkey, a young immigrant from America—who heightened Boyle’s interest in experimental chemistry.
Scientific career
Boyle spent much of 1652–54 in Ireland overseeing his hereditary lands, and he also performed some anatomic dissections. In 1654 he was invited to Oxford, and he took up residence at the university from c. 1656 until 1668. In Oxford he was exposed to the latest developments in natural philosophy and became associated with a group of notable natural philosophers and physicians, including John Wilkins, Christopher Wren, and John Locke. These individuals, together with a few others, formed the “Experimental Philosophy Club,” which at times convened in Boyle’s lodgings. Much of Boyle’s best-known work dates from this period. In 1659 he and Robert Hooke, the clever inventor and subsequent curator of experiments for the Royal Society, completed the construction of their famous air pump and used it to study pneumatics. Their resultant discoveries regarding air pressure and the vacuum appeared in Boyle’s first scientific publication, New Experiments Physico-Mechanicall, Touching the Spring of the Air and Its Effects(1660). Boyle and Hooke discovered several physical characteristics of air, including its role in combustion, respiration, and the transmission of sound.
One of their findings, published in 1662, later became known as “Boyle’s law.” This law expresses the inverse relationship that exists between the pressure and volume of a gas, and it was determined by measuring the volume occupied by a constant quantity of air when compressed by differing weights of mercury. Other natural philosophers, including Henry Power and Richard Towneley, concurrently reported similar findings about air.
Boyle’s scientific work is characterized by its reliance on experiment and observation and its reluctance to formulate generalized theories. He advocated a “mechanical philosophy” that saw the universe as a huge machine or clock in which all natural phenomena were accountable purely by mechanical, clockwork motion.
His contributions to chemistry were based on a mechanical “corpuscularian hypothesis”—a brand of atomism which claimed that everything was composed of minute (but not indivisible) particles of a single universal matter and that these particles were only differentiable by their shape and motion. Among his most influential writings were The Sceptical Chymist(1661), which assailed the then-current Aristotelian and especially Paracelsian notions about the composition of matter and methods of chemical analysis, and the Origine of Formes and Qualities (1666), which used chemical phenomena to support the corpuscularian hypothesis.
Boyle also maintained a lifelong pursuit of transmutational alchemy, endeavouring to discover the secret of transmuting base metals into gold and to contact individuals believed to possess alchemical secrets. Overall, Boyle argued so strongly for the need of applying the principles and methods of chemistry to the study of the natural world and to medicine that he later gained the appellation of the “father of chemistry.”
Theological activities
Boyle was a devout and pious Anglican who keenly championed his faith. He sponsored educational and missionary activities and wrote a number of theological treatises. Whereas the religious writings of Boyle’s youth were primarily devotional, his mature works focused on the more complex philosophical issues of reason, nature, and revelation and particularly on the relationship between the emergent new science and religion.
Boyle was deeply concerned about the widespread perception that irreligion and atheism were on the rise, and he strove to demonstrate ways in which science and religion were mutually supportive. For Boyle, studying nature as a product of God’s handiwork was an inherently religious duty. He argued that this method of study would, in return, illuminate God’s omnipresence and goodness, thereby enhancing a scientist’s understanding of the divine. The Christian Virtuoso (1690) summarized these views and may be seen as a manifesto of Boyle’s own life as the model of a Christian scientist.
Mature years in London
In 1668 Boyle left Oxford and took up residence with his sister Katherine Jones, Vicountess Ranelagh, in her house on Pall Mall in London. There he set up an active laboratory, employed assistants, received visitors, and published at least one book nearly every year. Living in London also provided him the opportunity to participate actively in the Royal Society.
Boyle was a genial man who achieved both national and international renown during his lifetime. He was offered the presidency of the Royal Society (in 1680) and the episcopacy but declined both. Throughout his adult life, Boyle was sickly, suffering from weak eyes and hands, recurring illnesses, and one or more strokes. He died at age 64 after a short illness exacerbated by his grief over Katherine’s death a week earlier. He left his papers to the Royal Society and a bequest for establishing a series of lectures in defense of Christianity. These lectures, now known as the Boyle Lectures, continue to this day.
It's fair to say that as divers Robert Boyle's work was pioneering and later gave us an understanding that enabled the sport of SCUBA to develop into what it is today. Boyle's law may be the first gas law we learn when we learn to dive but there are many more; Daltons, Henry's, Gay Lussac, Charles, the list goes on.
If your interested in learning more about gas laws and how they effect us as divers why not sign up to the SSI Science of Diving program? Contact us for details
The more you know, the more you grow - Never stop learning!