1. Read the text closely, define the main thought of each paragraph. Com­pose questions to each paragraph and be ready to answer your partner's ques­tions.

H. BOERHAAVE

Herman Boerhaave of Leiden lived from 1668 to 1738. He was a Newton's contempo­rary.

As a student he became interested in mathe­matics and other sciences and on receiving the degree of doctor of philosophy in 1690, went on to take the M.D. in 1693. At first he was not successful and began to work as a teacher, giv­ing lessons in mathematics. He also continued his various studies, paying particular attention to chemistry. At the age of 32 he became a lec­turer in the university, and delivered lectures on the theory and practice of medicine. He found that many students were deficient in scientific knowledge and so began to give private courses in mathematics, mechanics, phys­ics and chemistry. In 1709 he became professor of medicine and botany, in 1714 he also became professor of the practice of physics, physician to St. Augustine's Hospital and rector of the University. At the age of 50, he took' on the duties of the chair of chemistry as well.

For the next twenty years he remained in more or less complete control of teaching in medicine and the associated sciences. Boerhaave's reputation stood very high indeed during his lifetime and for many years afterwards. Something of this became known from the various anecdotes. A letter from the Far East ad­dressed simply to "M. D. Boerhaave, Physician in Europe" was delivered without difficulty.

His medical works were read by Japanese in their Latin originals, and he was in correspondence with the Dutch and obtained seeds for his studies of plants and for the development of the university botanic garden.

After Newton died in 1727 Boerhaave's name became the greatest among liv­ing men of science.

One of his main aims was to raise the status of chemistry to that of the ac­cepted academical sciences. In his theory he was concerned largely with inorga­nic materials and with physical chemistry and equally with vegetable, animal and mineral materials and with their physiological effects and importance in medical practice.

The Boerhaave's work on heat was also of great importance.

Fahrenheit of Amsterdam not only made special thermometers for this work but carried out some of the measurements for him. It is thus through Boerhaave that Fahrenheit scale became familiar and is still in use in many countries.

Of greater importance then the Fahrenheit thermometric scale was the ef­fort Boerhaave made to introduce quantitative methods of study. He gave several measurements of degrees of heat and cold produced by the solution of substances in water and especially during chemical reactions. In his experiments he demon­strated quantitative methods of study. At the time he began these demonstrations it was commonly believed that milk contained an acid, that the acid caused coagula­tion, and that to make it fluid again heat or alkalis should be used. To examine this Boerhaave took fresh cow's milk. Neither smell nor taste, nor dropping it in the eye revealed any acid or any alkalis. He then heated milk at 160° Fahrenheit and collected an aqueous liquor. It contained a yellow mass. It had a sweet and plea­sant taste, and gave no indication of the presence of acid or alkali. To demonstrate coagulation he diluted milk with a little water, brought it to the boiling point, and to portions of it added various mineral acids. Each time milk coagulated. Milk, he said, contained only little salt.

This is not an isolated example. Similar examinations were made of urine, blood, serum, egg albumen and other materials.

The full significance of Boerhaave's chemistry teaching was studied in many ways, especially in Scotland, France and Germany.