Un&,ersi~g of Pe,nnsylvania, Philadelphia,, Pen'ns:qlvania i. I'~troduelion By a co~tezt:}?ee mechanical language we mean one specified recursivety by a finite set of replacement ruled (a production system) of the form @~} ::= ~,:where each ~p~ is a finite concatenation of characters from a base alphabet (often ealled terminal characters, or vocabulary) and the alphabet of the @,} (often called nonterminal characters, or syntactic types) such that no ~b~ is the nullstring.Such a system generates strings of characters from the base alphabet called words of the language

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The purpose of this note is to analyze the conditions needed in geometry to introduce ideal points without using order relations. Since only incidence relations are used, it is convenient to use the notation of lattice theory. The actual introduction of the ideal elements is a purely algebraic process belonging to the theory of ideal extension and will be given elsewhere. (See abstracts 44-5-201, 45-1-16, 45-1-17.) Beside conditions already familiar in lattice theory we need conditions for the existence of products (see definition of cr-lattice) and the obviously necessary condition for projectivization, Condition E. The conditions for the existence of products are needed because incidence geometry is not taken to be a lattice ; in obtaining the projective extension it would be inconvenient to have to redefine the product of, say, two parallel lines; such a product, therefore, is left undefined. Condition E is not proved independent since our purpose is merely the elimination of considerations of order. Condition E has more force the greater the dimension of the space in which it operates. For dimension greater than 3 the development is consequently straightforward, so that we consider this case first. For dimension 3, however, Condition E appears to be a little too weak and we have a degenerate case requiring the use of the various forms of Desargues' theorem; the proof of these (D and D') requires an axiom on the existence of transversals, Axiom T. The three-dimensional case is put last, but in it the connection with the classical theory (see Pasch-Dehn, Whitehead, and Baker) is most apparent.

Leg ODP started numbering the scientific cruises of the JOIDES Resolution at Leg 101 (Leg 100 was a trial run of the modified drilling ship). Leg duration was nominally 2 months. The Shipboard Science Party typically consisted of 25 scientists drawn from universities, governments, and industry around the world. During the 18+ yr of ODP, there were 110 cruises on the JOIDES Resolution. T1. Prime data types, p. 118. ODP INFORMATION TECHNOLOGY AND DATA SERVICES ODP TECHNICAL NOTE 37 4 Site A site is the location where one or more holes were drilled while the ship was positioned over a single acoustic beacon. The drillship visited 656 unique sites during the course of ODP. Some sites were visited multiple times, including some sites originally visited during DSDP, for a total of 673 site visits. Hole Several holes could be drilled at a single site by pulling the drill pipe above the seafloor, moving the ship some distance away, and drilling another hole. The first hole was designated "A," and additional holes proceeded alphabetically at a given site. Location information for the cruise was determined by hole latitude and longitude. During ODP, 1818 holes were drilled or deepened. Core Cores are numbered serially from the top of the hole downward. Cored intervals are as long as 9.7 m, the maximum length of the core barrel. Recovered material was placed at the top of the cored interval, even when recovery was <100%. More than 220 km of core was recovered during ODP. Core Type All cores are tagged by a letter code that identifies the coring method used. Some of the more common core types are ODP INFORMATION TECHNOLOGY AND DATA SERVICES ODP TECHNICAL NOTE 37 9 Data Acquisition Many diagenetic changes occur in the uppermost 150 m of the sediment column, which was one of the reasons for higher density sampling of the uppermost 10-15 cores in a hole. During the first part of ODP, 25-to 30-cm whole-core OG samples were taken every 30 m and immediately frozen to preserve the core because of the volatile nature of organic matter. Not all analyses could be done in the shipboard chemistry laboratory, and freezing these samples slowed deterioration of the organic matter and minimized chances of contamination. Shipboard scientists stopped taking OG samples after Leg 134, probably because they were able to collect the information they needed and there were few requests for OG samples for shore-based studies. Analyses of samples produced data as weight percentages of total carbon, inorganic carbon, and organic carbon directly or by difference. Although other carbonates may be present, all acid-soluble (i.e., inorganic) carbon was reported as calcium carbonate. In addition, analyses sometimes included data for elemental concentrations of sulfur, nitrogen, and hydrogen. These data were used to characterize the nature of the organic carbon. Samples taken for carbon analysis were freeze-dried, crushed, and carefully weighed. If the sample was to be analyzed for carbonate, the sample was mixed with acid to convert the carbonate to CO 2 b...