The charophyte Lamprothamnium succinctum as an environmental indicator: a Holocene example from Tom Thumbs Lagoon,eastern Australia

The palaeobiota from a middle to late Holocene succession in Tom Thumbs Lagoon, N.S.W., Australia, reflects a range of environmental conditions caused by sea-level changes and active estuarine sedimentation. At the base of the succession (～ ?0.4 m AHD) a thin bed, containing molluscs dated at 6.7 ka B.P. by radiocarbon and amino acid racemisation, and foraminifers is indicative of open estuarine conditions. From +0.35 m AHD towards the top of the sequence the charophyte Lamprothamnium succinctum occurs in subrecent deposits. This species is characterised here by statistical measurements, and new characters are described and illustrated. The charophytes record a drop in sea level and the establishment of a lower salinity artificial wetland. The investigation has also established that decalcification in charophytes can be related to acidification produced by the release of organic acids, aggravated after 1928 by anthropogenic pollution.     

Shelley’s “Letter to Maria Gisborne” as Workshop Poetry

ABSTRACT

Shelley’s “Letter to Maria Gisborne” is a playful improvisational verse epistle, widely praised for its urbanity and its display of the poet’s invention. The verses turn on a catalogue of the collection of odd scientific and mechanical objects that Shelley found scattered around him in the place he composed the letter, the Livorno workshop of Gisborne’s son, a young engineer who was building a new-model steamboat at the time (with Shelley’s financial and intellectual backing). In the context of that space, the poem reads as a response to competing notions of invention. For Shelley, the engineer’s workshop is an attractive alternative to the poet’s tower—which was uncomfortably close to a Grub Street garret. Verbal and visual images of poets’ and scientists’ workshops, from Hogarth and Mary Robinson, to Joseph Wright of Derby and Frankenstein, illustrate the tensions embodied in the physical location and poetic performance of Shelley’s celebrated “Letter.”     

Induced metal-ion exchange in excavated human bone

Excavated human bone was exposed to aqueous solutions containing high concentrations of a single added metal ion in order to examine the extent of introduction of contaminating materials during burial. Variables included pH, temperature, ion concentration, state of bone (whole or crushed), structure of buffer, and counterion. Calcium and sodium showed little increase, and even a decrease in some cases. Strontium, zinc, lead, and magnesium showed large increases probably through heteroionic replacement of calcium. Manganese, aluminum, and potassium showed increases, particularly under neutral conditions, probably through infiltration into voids and defects.