An astrolabe from Passa Pau, Cape Verde Islands

Mariner's astrolabes seem to have been in use from the 15th to the end of the 18th centuries. They evolved at about the same time as quadrants and cross-staffs. Their precursor, the astronomer's astrolabe and kamal, were either too cumbersome or not sufficiently accurate for sea-going use. An astrolabe found on the Passa Pau wreck is unique in that it is the only know/specimen coated with silver. It is dated 1645 and has the maker's name, Nicolao Rvffo, inscribed on it.     

Beached Shipwrecks from Channel Islands National Park,California

Abstract

Three shipwreck sites of the 19th century in Channel Islands National Park, California form case studies in evaluating the contribution of beached shipwrecks to maritime and historical archaeology. Two of the sites are consistent with the historically-documented Pacific coast lumber schooners J. M. Colman and Dora Bluhm, but the archaeological record is sparse. Material remains are compared to primary documents, such as original 19th-century construction contracts and insurance classifications, to make a case for the beached shipwreck scatters belonging to these ships. A third site, Comet, presents the other end of the spectrum; its remains have been conclusively identified by historical photographs and the site is a partially-intact hull embedded in the beach sand. This site was also recorded in detail and the formation processes of all three sites were examined to aid in archaeological interpretation.     

Neolithic Pottery Traditions from the Islands, the Coast and the Interior of East Africa

Scholars have attributed the spread of agriculture and pottery technology to the larger part of eastern and southern Africa to Bantu speakers. However, the spread of similar aspects to the Kenya and Tanzania Rift Valley as far south as Eyasi Basin and as far east as Mount Kilimanjaro has been attributed to Cushitic speakers. Whereas the spread of these innovations to the Rift Valley region can be dated back to 3000 BC, the remaining part of eastern and southern Africa is alleged to have received similar innovations only after the BC/AD changeover, when iron technology was introduced. These theories can no longer be sustained. The coast of Tanzania, its immediate hinterland, and the deep sea islands of Zanzibar and Mafia were settled by people who had knowledge of agriculture and pottery making probably from 3000 BC. These innovations are also found to have spread to southern Africa in the last millennium BC. The introduction of iron technology and beveled/fluted pottery, associated with Bantu speakers, was just another stage in the cultural evolution of the people of eastern and southern Africa, but not the beginning of settled, farming/domesticating communities.La diffusion de l'agriculture et la technologie de poterie à la région plus grande de l'Afrique orientale et méridional ont était attribué au parleurs des langues bantou. Cependant, la diffusion des aspects semblables au Rift Valley de Kenya et Tanzania, sud au Bassin d'Eyasi et est au Mont Kilimanjaro ont était attribué au parleurs des langues Cushitic. Tandis qu'on peut dater la diffusion de ces innovations à la région du Rift Valley à 3000 BC, il est prétendu que la région restante d'Afrique orientale et méridional ont reçu les innovations similaires seulement après le changement de BC/AD, au temps que la technologie de fer était indroduit. Il n'est pas possible maintenant à sustenir ces théories. La côte de Tanzania, son hinterland immédiat/les regions près de la mer, et les îles de Zanzibar et Mafia, ont étaient colonisé par les personnes qui avait la connaissance de l'agriculture et de la poterie probablement à partir de 3000 BC. On peut trouver aussi que ces innovations ont diffusé à l'Afrique méridional pendant la dernier millénaire avant J. -C. L'introduction de la technologie du fer et la poterie avec le biseau, liée avec les parleurs des langues bantoues, était seulement un autre étape dans l'évolution culturelle du peuple de l'Afrique orientale et méridional. Il n'était pas le commencement des communautés établis qui ont pratiqué l'agricole et la domestication.