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For 41 soils (pH > 5.0), the Langmuir equation was an excellent model for describing P adsorption from solutions < 10-¯³M P, if it was assumed that adsorption occurs on two types of surface of contrasting bonding energies. In most of these soils, which were very undersaturated with P, > 90% of the existing adsorbed P occurs on the high energy surface. However, the adsorption capacity of the low-energy surface is usually at least double that of the high-energy surface. In 24 calcareous Sherborne soils, the specific surface areas of the carbonate component were an inverse hyperbolic function of the CaCO₃ content, and ranged from 16 to about 500 m²/g. The total surface areas were a slightly inverse and linear function of the CaCO₃ content, and ranged from 4 to 8 m²/g soil. In multiple regression studies on the Sherborne soils, high-energy P adsorption capacity was mainly associated with dithionite-extractable Fe (r² = 0.81), while pH had a large negative effect (r² = 0.71). Low-energy P adsorption was most closely correlated with organic matter content (r² = 0.53) and CaCO₃ surface area (r² = 0.46). From these results, together with results of P adsorption studies on the limestone parent materials, it was postulated that low-energy P adsorption occurs on CaCO₃ surfaces on which organic anions already occupy alternate adsorption sites. The Langmuir equation was used to calculate the theoretical maximum buffer capacities and the equilibrium buffer capacities of two different groups of soils. In multiple regression studies with P intensity or quantity measurements, these estimates of buffer capacity accounted for up to 94% of the variance in P uptake by ryegrass on these soils. The results showed that when soil P is measured as quantity, its availability (ie ease of desorption) is inversely related to the Langmuir bonding energy parameter and the buffer capacity. When measured as intensity, its 'availability' (ie resistence to change) is directly related to the adsorption capacity and buffer capacity.

Allergens of animal origin derived from domestic mammals such as cats and dogs, and from the mite Dermatophagoides pteronyssinus, living in house dust, are common causes of asthma and rhinitis in Britain. These allergens have been investigated using extracts of cat, dog and horse skin and of cultures of a related species of Dermatophagoides, D. farinae, and determining their activity by skin tests. The allergens of D. farinae generally had a higher carbohydrate content than those of the mammalian skins; they showed different behaviour on precipitation with trichloroacetic acid and with ammonium sulphate and were less susceptible to proteolytic digestion. The major allergens of all four extracts showed anodic electrophoretic mobility at alkaline pH, and behaviour on ion exchange cellulose chromatography consistent with an acidic nature. Certain heterogeneity of allergenic activity was apparent, in that minor allergens occurred in fractions distinct from those containing the major allergens. This was noted particularly in the fractions obtained from Sephadex G-200 gel filtration of the mammalian skin extracts. Minor allergens, which were important in certain patients, were obtained in high molecular weight fractions and showed activity mainly in those patients highly sensitive to serum proteins. Fractions have been prepared, by gel filtration on Sephadex G-200, which contained the major allergens of the mammalian skins and of D. farinae. They were eluted between protein markers of molecular weights 24,000 and 67,000, the major allergens of the mammalian skins having a somewhat higher molecular weight than those of D. farinae, and thus showed similarities to allergens of many other common inhaled materials which have molecular weights of 25,000 to 40,000.

The book studied consists of thirty unrelated chapters covering natural, ethical, and dialectical philosophy, Roman history, Latin phonology, lexicography, literary criticism, and various other matters. The thesis is primarily intended as a Sachkommentar elucidating the things discussed or mentioned in the chapters; but it also considers points of text or Latin usage, and especially of Gellian Latinity. The commentary takes the form of a running annotation on each chapter, with introductory notes and excursus wherever they seemed desirable. It is assumed the reader has to hand the editions by Hertz (ed.maior), Hosius, and Marshall; information given by them (e.g. on the provenance of citations) is in general not repeated. The text followed is Marshall's, save as otherwise stated; questions of text settled by Hertz or his predecessors are normally omitted, being adequately covered in his apparatus. A commentary of this nature on an author of this nature can hardly have a unifying theme to be abstracted and summarized: it must inevitably consist of individual discussions, some longer than others. Among the longer discussions may be noted those on ancient wind-roses, and the peculiarity of that described by Favorinus (Gell.2.22, introductory note); the history of Roman attempts to curb the luxury of the table (2.24 excursus); the use of the adjective cuius(2.29.15), which is shown to have been regular in Early Latin as a predicate, but rarely used as an attribute save in legal language. It is also shown (2.3.5n) that Gellius's references to allegedly autograph Vergils are of no value to the critic save as attesting ancient variants. In passing, an attempt is made to explain an anachronism in Claudius Quadrigarius (Gell.2.2.12-13n). The most important textual discussion is that in the excursus to 2.23, where the fragments of Menander and Caecilius cited in that chapter are treated in detail and several new suggestions made about them. In Gellius himself a few proposals are made, mostly of deletion; at 2.1.2, for instance, Socrates is expelled from the text. Although the excursus to 2.17 is devoted to the demolition of Hosius's argument that the chapter was derived from Probus, not much attention is bestowed on Quellenforschung; this is due to scepticism concerning the assumptions on which that operation has been conducted. Attacks on these assumptions will be found in the prolegomena (pp. 23-32); in the course of this discussion it is concluded that of the various anecdotes Gellius tells about his friends and teachers, some are true, some are composed around their writings, and some are utterly fictitious. These prolegomena are not a full-scale introduction, but confine themselves to certain points such as Gellius's name (for which the evidence is set out in detail, pp.3-7) and the date of the Attic Nights' publication (which is set c.179 A.D. pp.8-12). The claim that the Nights are meant to be morally useful is examined and largely dismissed (pp.13-22); although the archaistic movement is not discussed in detail, passages from Gellius and Fronto apparently running counter to it are shown to be warnings against untimeliness and ostentation (pp. 33-36). There is a brief account of the manuscripts in which Book 2 is found (pp.36-39), and a review of the principal editions, commentaries, and translations (pp. 40-44).