Puzzles and codes have multifaceted uses in practices of concealment, especially for militaristic purposes, corporate secrecy, or national security.The term ‘Enigma’ is perhaps most recognisable in modern history and contemporary culture as the name of a cipher device used by the German military to send messages during World War II. This chapter moves to the historical context of the twentieth century and shows how humans sometimes deliberately engineer enigmas to serve their own purposes. The author focuses on the mathematics underpinning the story of the Enigma Machine, setting out the process both of the code’s creation and of its decryption. Following the story of Alan Turing, a mathematician and one of the code breakers at Bletchley Park, the chapter emphasises both the necessity of collaborative labours to solve challenging problems and the importance of individual research and investigation to resolve crucial pieces of a much larger puzzle.

A new therapy that uses the patient's own blood to cure blood cancers (leukaemias) is the focus of this chapter. The history of its detection and diagnosis is related, along with the long and arduous search for effective treatment, arriving at successful employment of bone marrow transplantation in the later twentieth century. More recent developments in chemotherapy are reviewed, leading to a contemporary account of the encouraging progress with T-cell therapies.

In this chapter the author probes beneath the melodramatic surface of the story of Count Dracula, to reveal more subtle narrative threads, relating to Bram Stoker's critical social observations, both looking back in time, where many metaphorical dimensions of ‘blood’ are in play, and forward in time to late-nineteenth-century changes in gender relations, particularly as encapsulated in the figure of the ‘New Woman’. Just as blood-steeped history is conspicuous on the melodramatic surface of the fiction, so a forward-looking, scientific, and liberated future is discernible just beneath that surface.

This chapter explores the historical evidence for cultural attitudes to menstruation. The most commonly promoted medical theories as to why women experienced a monthly bleed are discussed. The many words and circumlocutions early moderns used to describe menstruation and related female reproductive bleeding are considered, along with prevailing cultural expectations about this event.

This chapter starts with a historical review of ideas about blood flow around the body, culminating in an understanding of circulation, the mechanics of which are described. The propagation of the pressure pulse in arteries is discussed, as is the disturbance to smooth flow caused by the complex geometry of arteries. The deformation of blood cells during their passage along the smallest capillaries is considered, as are the interesting effects of gravity on the venous return to the heart in upright animals, notably those with long necks and legs, such as giraffes and dinosaurs.

The editors recount how the volume came about and the choices that were made to invite contributors. The themes of the volume are discussed, both those in the organisers’ minds at the start, and those that emerged during the course of the lecture series.

This chapter explores different forms of thermoregulation of blood in animals living in a range of contrasting environments, from the Kalahari Desert to the Antarctic ice. In a wide diversity of species, a range of anatomical adaptions are considered, including heart and blood vessels morphology, natural insulation, and as behavioural and life-cycle adaptations. The strategies of endotherms and ectotherms are compared, and the very particular biology of the icefish is considered.

The chapter opens with a concise history of the recognition of blood types that, as well as informing the human immune system, incidentally provide an ideal genetic data set for phylogenetic enquiry. The chapter goes on to relate that enquiry to the author’s People of the British Isles project. This project draws upon genetic data from just over 2,000 volunteers to construct a genetic map of the human population of the British Isles. From that genetic map, the peopling of the British Isles is inferred and reconstructed.

Blood as the foundation of life and health is the focus of this chapter, which assembles a series of heroes and villains in the quest for good blood health. The heroes comprise a pioneer of the blood transfusion service and a designer of economic sanitary pads; the villains comprise an experimenter on the accident-strewn path to mastery of life-saving (rather than life-taking) transfusion.

In conversation with one of the editors (Iosifina Foskolou), Marc Quinn discusses his life and practice as an artist, and how that brought him to work with blood. After discussing the technical challenges of sculpting with blood, the conversation moves to notable artworks, including: Self, Our Blood, Breath, and A Surge of Power.

In September 1618, when he was almost 30 years old, Isaac Beeckman made some biographical entries in his notebook. From the age of 21, he recollected, he had devoted himself ‘more than a little’ to mechanical operations. During the 1610s, having set up shop as a candle maker in Middelburg and Zierikzee, Beeckman was engaged in all kinds of projects involving conduits, pumps, and fountains. First assisting his father, he soon took on work of his own. These activities turn up in his notebook in reflections upon hydrological machines, but also chimneys and stoves. After he moved to Utrecht and Rotterdam and became a schoolmaster, the waterworks did not disappear from the notebook, but the emphasis shifted from technical installations to curious apparatus like thermoscopes and perpetual motion machines.

This chapter focuses on Beeckman's engagement with such atmospheric instruments in his Rotterdam period (1620-1627). Both the contents and the epistemic significance of his notes on these topics have not been studied in much detail. They shed an interesting new light on his learned persona and put him in a new historical context related to late-sixteenth-century meteorology. The notes on atmospheric instruments show a kind of reasoning that I call ‘artefactual’: getting a conceptual grip on matters by tinkering with and reflecting upon artefacts like thermoscopes and stoves. This aspect of Beeckman adds, I maintain, to our understanding of his learning and his place in the early-seventeenth-century history of science.