This chapter begins with the demise of the 25 Meter Telescope proposal. The subsequent actions of the US millimeter astronomy community and the National Science Foundation lead to the formation of a committee to advise on the next steps. The Barrett Report has several recommendations, the most significant of which is the development of a large millimeter wavelength array. The first concept for such an array, also the first concept for ALMA, is presented.

This chapter describes the millimeter array projects under development in Europe and Japan and how the Millimeter Array and European Large Southern Array agreed to pursue a joint project.

The organization of the joint millimeter array project, now called ALMA, is presented from its informal beginnings to the ALMA Coordinating Committee and ALMA Board. The issues discussed by these bodies are presented for a selection of significant meetings.

This chapter explains how ALMA has met its key science goals. The early science results are presented along with summaries of ALMA's science productivity over its first 10 years of operation. The reader learns how one proposes for observing time. The role of the regional ALMA science centers is set out. The prospects for the future enhancement of ALMA are discussed.

The search for the best site for the Millimeter Array is the subject of this chapter. It begins in the continental United States, moves to Mauna Kea in Hawaii, and ends in the Atacama Desert of northern Chile. After detailed study, the Chajnantor site above the village of San Pedro de Atacama is approved. Protection of the site is secured from mining claims, a gas pipeline, and radio interference.

The ALMA Board discussions of difficult issues to resolve are presented in this chapter. A detailed account of the purchase of prototype and production antennas is given. The long route to Japan's entrance into ALMA is given. How the issues were settled of who would employ the ALMA staff in Chile and where the ALMA Observatory headquarters would be located in Santiago is set out.

We saw in the last chapter how the Heronian tradition fragmented and flourished in the Byzantine and medieval Islamic worlds. Yet in the Latin west, Hero’s trail went quite cold during this period. A few references suggest that he continued to be characterized as he was in Pappus, as a mechanical author and pneumatic wonder-worker. In the Summa Philosophia of the Pseudo-Grosseteste, Hero is named as an egregius philosophus who strove to demonstrate the void “through clepsydras and siphons and other instruments.”1 Henricus Aristippus recommends in the preface to his 1156 translation of the Phaedo that his pseudonymous addressee elect to stay in Sicily, where he has access to a rich library of philosophical and scientific texts, including “the mechanica of the philosopher Hero … who argues so subtly about the void.”2