Carn Alw as a source of the rhyolitic component of the Stonehenge bluestones: a critical re-appraisal of the petrographical account of H.H. Thomas

The source of the Stonehenge bluestones was first determined in the early 1920s by H.H. Thomas who was an officer with the Geological Survey of England and Wales. He determined that the so-called ‘spotted dolerites’ could be petrographically matched to a small number of outcrops in the Mynydd Preseli district in south-west Wales. The bluestones, however, comprise a number of additional lithologies, including rhyolite and ‘calcareous ash’, as well as various sandstones. Thomas was convinced that the volcanic lithologies in the bluestone assemblage were all sourced from a small area at the eastern end of the Mynydd Preseli, with the rhyolites originating from the prominent outcrop known as Carn Alw. Recently, provenancing of these rhyolites to Carn Alw has been questioned on the evidence of whole-rock geochemistry. This raised concerns over the original petrographical attribution. Accordingly a re-investigation was undertaken of the rhyolite petrography by re-examining the original specimens used by Thomas. Three of the original four thin sections studied by Thomas were re-examined, along with a newly made thin section from the fourth of Thomas' rock samples as the original thin section could not be located. The new petrographical evidence demonstrates convincingly that the two pairs of thin sections from the Preseli and Stonehenge as examined by Thomas do not match despite his contention and argues strongly that Carn Alw is not the source of the Stonehenge rhyolites which Thomas described. This reinforces the geochemical evidence presented recently and supports the contention that Craig Rhos-y-felin, to the north of Mynydd Preseli, is an important source of rhyolitic debris in the Stonehenge Landscape. Nevertheless, there remain uncertainties over the provenance of other Stonehenge rhyolites (and dacites), including four of the orthostats themselves.     

A Crocean critique of Gramsci on historicism,hegemony and intellectuals

Although Gramsci's debt to Croce is well known, most commentators simply accept his criticisms of Croce and his claim to have overcome certain lacunae in the Neapolitan's thought. This article argues that many of these criticisms misfire, and mounts a Crocean critique of Gramsci. Through a comparison of their respective views of historicism, hegemony and intellectuals, it is argued that the radical democratic and libertarian theory many post-Marxists claim to find in the Sardinian is more appropriately associated with Croce. Sebbene il debito di Gramsci verso Croce sia risaputo, molti commentatori tendono semplicemente ad accettare le critiche di Gramsci verso Croce, in particolare il primato da parte di Gramsci stesso nell'aver colmato certe lacune nel pensiero del filosofo napoletano. Questo articolo pone in rilievo che molti di queste critiche risultano essere prive di significato, ed inoltre, tende a far emergere una critica crociana di Gramsci. Dal tentativo di porre in relazione le idee di entrambi su concetti quali lo storicismo, l'egemonia, ed infine l'identitÀ degli intellettuali, si evince che la teoria libertaria e democratico-radicale che molti post-marxisti tendono ad attribuire all'intellettuale sardo, tende ad essere in buona parte il prodotto del pensiero di Croce.