THE ECONOMIC LAW OF MARKET AREAS: A FURTHER DISCUSSION*

ABSTRACT. The Economic Law of Market Areas, so named by Fetter, is concerned with the division of a territory between two competing centers. It is argued that this Law can be conveniently examined in terms of six cases, each of which is specified by a combination of differentials in freight rates and prices at the two centers. The locational significance of each case is considered, along with the form and dimensions of the market-area boundary between the two centers. Three of the cases are each shown to subsume a special case. It is further shown that for any case except one, a reversal of the differentials between the two centers, while resulting in a symmetrically-equivalent outcome, requires a different (and usually substantial) respecification of the case.     

THERMOLUMINESCENCE DATING OF POTTERY: AN ASSESSMENT OF THE DOSE-RATE FROM RUBIDIUM

The naturally occurring radioisotope ⁸⁷Rb makes a small contribution to the total dose-rate. Assuming an average potassium:rubidium ratio of 200:1 the contribution is estimated at 2.9% of the B dose-rate From potassium. The effect will be negligible in quartz inclusion dating because of the strong attenuation of the B- emission from ⁸⁷Rb. In fine-grain dating the omission of the ⁸⁷Rb contribution will overestimate the age of a pottery sherd by not more than 2% and this is regarded as of minor importance when the total error in the technique is at least 15%.     

OBSIDIAN HYDRATION DATING: AN IMPROVED OPTICAL TECHNIQUE FOR MEASURING THE WIDTH OF THE HYDRATION RIM

A simple optical method is described that will enhance the color contrast between the outer birefringent hydration rind and the inner unhydrated core on obsidian thin sections used for hydration dating. The technique utilizes a gypsum nccessory plate. The gypsum plate rotates all incoming light by 550nm causing the black isotropic core of the nhsidian to become transparent first-order pink and interacting with the transmitted light from the birefringent rind, by either addition or subtraction. to produce a second-order blue or a first-order yellow color.     

评《蒋祈〈陶记〉著作时代考辨》——与刘新园先生商榷

一前言《陶记》是中国第一部有关陶瓷生产技术、管理及其行销等方面的论著,对其进行深入的理解和断代有益于中国陶瓷史、科技史的研究,故我国老一辈陶瓷研究学者傅振伦、陈万里、冯先铭等先生都对《陶记》给以关注,傅振伦先生在耋耄之年(1979年)还对《陶记》进行了译注。约与《陶记》同时期,伊朗人阿布尔·卡西姆于1301年著有《阿布尔·卡西姆有关陶瓷的论     

THE CHRONOSTRATIGRAPHY AND GEOARCHAEOLOGICAL SIGNIFICANCE OF AN ALLUVIAL GEOARCHIVE: COMPARATIVE OSL AND AMS 14C DATING FROM GREECE*

The Basin of Phlious in southern Greece is known for its thick colluvial and alluvial deposits from the Holocene. It offers a good opportunity to reconstruct the history of Holocene soil erosion and its interaction with historical farming activities. In this study, we present new results based on optically stimulated luminescence (OSL) dating from the Basin of Phlious. The comparison between OSL and ¹⁴C AMS ages shows good agreement, and demonstrates the need for the detection of insufficiently bleached OSL samples in order to obtain accurate results. The discovery of a Neolithic site, buried under thick alluvial deposits, confirms the hitherto postulated Neolithic human impact on the landscape.