The wash bottle

Washbottles, old (left, photo: Hannes Grobe) and new (right).

Wash bottles, in one form or another, have been a long-term feature of the chemistry lab. Once they were made of glass, and were operated by blowing. In more recent times, plastic squeeze bottles have been used.

See here for more posts on scientific equipment.

Angélique du Coudray, pioneer midwife

Angélique du Coudray

Angélique du Coudray (c. 1714–1794) was a pioneering French midwife. In 1759 she published a midwifery textbook, Abrégé de l’art des accouchements. Her introduction notes the fact that incompetence or lack of care can lead to the death of both mother and child, and continues with a politico-religious imperative: “Ignorons-nous que ces deux viâimes étoient chères aux yeux de Dieu, utiles à leur famille, & nécessaires à l’État? C’étoit un dépôt qui nous avoit été confié. Pouvons-nous, en les sacrifiant à un vil intérêt, ne pas trembler sur le compte exact que nous en rendrons un jour à celui qui leur avoit donné l’être?” (“Do we not know that these two lives were dear to the eyes of God, useful to their families, and necessary to the State? They were a deposit which was entrusted to us. Can we, if we sacrifice them to a vile interest, not tremble at the exact account that we shall one day render to Him who gave them to be?”).

To avoid such deaths, du Coudray explains proper prenatal care, and provides instruction on both normal deliveries and a range of common obstetric problems.

Illustration of a normal delivery, from the 1777 edition of Abrégé de l’art des accouchements

Also in 1759, Angélique du Coudray was commissioned by King Louis XV to tour the country training midwives, in the hope of reducing perinatal mortality. She personally trained thousands of midwives, many of whom went on to train others. Her training course was assisted not only by her book, but also by her Machine, a pioneering lifesize obstetric simulator. The Machine included realistic internal structure, such as bones and ligaments, and could be used to practice delivery of a baby in a range of different positions, while giving the trainee midwife a feel for the forces involved.

Angélique du Coudray’s Machine (photo: Ji-Elle)

The Museum of the History of Science, Oxford

Museum exterior (Old Ashmolean Building)

The Museum of the History of Science in Oxford holds a spectacular collection of thousands of early scientific instruments, such as the microscope below. The Museum can be visited on afternoons (except Mondays) for those fortunate enough to be in Oxford, but there is an excellent virtual tour, so that people from around the world can explore what the Museum has to offer. There are also many online exhibits and several YouTube videos. Few museums have an online presence this good. Even the shop is online!

Microscope and accessories (photo by Mark Harding)

For more information, see the museum website or the Wikipedia article.

The Bunsen burner

The Bunsen burner was invented in 1855 by the German chemist Robert Bunsen at the University of Heidelberg, assisted by Peter Desaga, an instrument maker there. Bunsen wanted a device that could produce heat without light, unlike the gas flames used for lighting at the time.

Bunsen was particularly interested in using the burner to identify elements by the colour of the flame they produced (or, more precisely, to identify elements by their emission spectrum). The image above shows the flames produced by placing salts of lithium, sodium, potassium, and copper in the flame of a Bunsen burner, for example. The image below shows the corresponding emission spectra (from top to bottom: Li, Na, K, Cu).

Mohr’s burette

The burette, an important volumetric tool, was invented by Karl Friedrich Mohr somewhere around the middle of the 19th century. There had been other devices carrying the name “burette,” but they required pouring. Mohr introduced a rubber tube with a clamp that allowed the gradual drop-by-drop flow needed for titration (the clamp was later replaced by a tap). Mohr’s 1855 book on titration, which illustrated the device, helped it to become the key item of analytical equipment it still (in spite of more modern digital devices) is today. Thanks, Karl!

Once again, a Google ngram summarises the history, with the word “burette” rapidly gaining popularity from 1855, but being replaced by the word for the process, which itself faded after 1960 – perhaps because of the growth of other kinds of science.

The Petri dish

The Petri dish (photo above by “Lilly M”) has been of great benefit to microbiologists wishing to culture bacteria. The Petri dish was invented by the German microbiologist Julius Petri (1852–1921), a colleague of Robert Koch. In 1887, Petri wrote a paper describing how bacteria could be grown on a layer of gelatin in such a dish.

The use of agar in Petri dishes dates from 1881, when Fanny Hesse, wife of Walther, suggested its superiority to gelatin. Frau Hesse apparently used agar for cooking, as a result of having friends from what was then the Dutch East Indies (“agar” is a Bahasa word).

Petri dishes are also useful for studying reactions such as the Belousov–Zhabotinsky (BZ) reaction in thin liquid layers:

The Macleay Museum, Sydney

The Macleay Museum (interior)

The Macleay Museum is a small (but free!) museum tucked away in the top floor of the Macleay building at the University of Sydney.

The museum, begun two centuries ago by Alexander Macleay, specialises in animal specimens and old scientific instruments, as well as having an ethnographic collection. However, only a handful of specimens are on display to the casual visitor. Still, like the other University of Sydney museums, the Macleay Museum is well worth a brief visit.

A microscope from the Macleay Museum’s collection

Update: the Macleay Museum will be closed for renovations from 25 November 2016 until 2018.

The alembic

The alembic, illustrated above, is an ancient item of laboratory equipment. As with algebra, Alnitak, and alizarin, the Arabic definite article in the name indicates a borrowing from the Islamic world.

The device seems to date from then-Christian Alexandria (Egypt) in the first few centuries AD. The Greek word ἄμβιξ (ambix) led to the Arabic الأنبيق (al-anbīq) and hence via Latin to the English word.

The Google ngram above shows the decline in popularity of the English word since 1700. We now have more sophisticated distillation equipment, after all. Farewell, alembic!

The Erlenmeyer flask: 153 years and counting

The Erlenmeyer flask (photo above by “Lucasbosch”) is much used by chemists everywhere. It was invented by the organic chemist Emil Erlenmeyer around 1860. The flask facilitates swirling or shaking, is spill-resistant, can be placed on a flat surface, and allows a stopper to be placed in the neck. A versatile piece of equipment: thanks, Emil!