Adair Crawford FRS  a chemist and physician, was a pioneer in the development of calorimetric

Calorimetry

Calorimetry is the science of measuring the heat of chemical reactions or physical changes. Calorimetry is performed with a calorimeter. The word calorimetry is derived from the Latin word calor, meaning heat...

 methods for measuring the specific heat capacity of substances and the heat of chemical reactions. In his influential 1779 book "Experiments and Observations on Animal Heat", Crawford presented new experiments proving that respiratory gas exchange in animals is a combustion (two years after Antoine Lavoisier

Antoine Lavoisier

Antoine-Laurent de Lavoisier , the "father of modern chemistry", was a French nobleman prominent in the histories of chemistry and biology...

's influential "On combustion in general"). Crawford also was involved in the discovery of the element strontium

Strontium

Strontium is a chemical element with the symbol Sr and the atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when exposed to air. It occurs naturally in the minerals celestine and...

.

Life

Adair Crawford was born near Belfast

Belfast

Belfast is the capital of and largest city in Northern Ireland. By population, it is the 14th biggest city in the United Kingdom and second biggest on the island of Ireland . It is the seat of the devolved government and legislative Northern Ireland Assembly...

 and studied medicine at Glasgow

University of Glasgow

The University of Glasgow is the fourth-oldest university in the English-speaking world and one of Scotland's four ancient universities. Located in Glasgow, the university was founded in 1451 and is presently one of seventeen British higher education institutions ranked amongst the top 100 of the...

 and Edinburgh

University of Edinburgh

The University of Edinburgh, founded in 1583, is a public research university located in Edinburgh, the capital of Scotland, and a UNESCO World Heritage Site. The university is deeply embedded in the fabric of the city, with many of the buildings in the historic Old Town belonging to the university...

 universities. He was Professor of Chemistry at the Royal Military Academy, Woolwich, London, and physician at St Thomas' Hospital

St Thomas' Hospital

St Thomas' Hospital is a large NHS hospital in London, England. It is administratively a part of Guy's & St Thomas' NHS Foundation Trust. It has provided health care freely or under charitable auspices since the 12th century and was originally located in Southwark.St Thomas' Hospital is accessible...

, London. He died at Lymington

Lymington

Lymington is a port on the west bank of the Lymington River on the Solent, in the New Forest district of Hampshire, England. It is to the east of the South East Dorset conurbation, and faces Yarmouth on the Isle of Wight which is connected to it by a car ferry, operated by Wightlink. The town...

 in Hampshire.

It is no coincidence that the titles of his publications usually begin with the word experiments. Crawford let the details of his experiments and their plain results do the talking, and generally refrained from theorizing and over-interpretation. He did maintain the later-discredited phlogiston hypothesis

Phlogiston theory

The phlogiston theory , first stated in 1667 by Johann Joachim Becher, is an obsolete scientific theory that postulated the existence of a fire-like element called "phlogiston", which was contained within combustible bodies and released during combustion...

, but wasn't doctrinaire about it.

Calorimetric work

Crawford's book "Experimental Enquiry into the Effects of Tonics and Other Medicinal Substances on the Cohesion of Animal Fibre", written near the end of his life, offers a very readable presentation of his way of doing chemistry. Here's an example:

With a view to determine the changes which animal fibre might undergo by exposing it to the action of Port wine, six portions of the small intestines of a kitten were taken. Three of these were introduced into a phial, which was nearly filled with Port wine, and closed with a cork; and the remaining three were immersed in water, as a standard. Being placed in a cool situation during three days, the portions in contact with the wine were found to have greater firmness than those that were immersed in the water. The sum of the weights required to break the former was 9 lb. 0 oz.; the sum of those required to break the latter was 7 lb. 4 oz. .... With a view to guard against error in trials of this nature, it is of importance that the portions of the intestine should be as nearly as possible of the same length. They should likewise have nearly the same degree of curvature. For a very curved portion of the intestine is more easily broken than a straight one.... If the trials be frequently repeated, results will be obtained that approach near to the truth.... From the foregoing trials, it appears, that the firmness, elasticity, and strength of the intestines of a kitten are considerably increased by immersing them three days in Port wine. I have found, however, that a much less time than this is sufficient for the wine to produce its full effect. In several experiments a manifest increase of cohesion appeared to have taken place in less than an hour; and after ten hours have elapsed, I believe no farther augmentation is produced.

Discovery of strontium

In 1790, along with his colleague William Cruickshank

William Cruickshank (chemist)

William Cruickshank was a Scottish military surgeon and chemist, and professor of chemistry at the Royal Military Academy, Woolwich.-Career:...

 at the Royal Military Academy, Woolwich, London, Crawford noted the distinctiveness of strontianite

Strontianite

Strontianite is an important raw material for the extraction of strontium. It is a rare carbonate mineral and one of only a few strontium minerals...

 from barium

Barium

Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Barium is never found in nature in its pure form due to its reactivity with air. Its oxide is historically known as baryta but it reacts with...

 minerals, and may thereby be said to be the discoverer of strontium. However, it could also be claimed that the honour should go to Humphry Davy

Humphry Davy

Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...

who, in 1808, became the first to isolate the pure element.

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