In dating the samples reported here as well as in calculating their ages, the same equipment and method of processing and counting were used which were previously described in Tartu I and II.

The C14 dates presented here were obtained by counting methane, using the technique described earlier (Agrawal et al., 1965a). In accordance with the decision of the Sixth Pullman Conference (Internat. Gonf., Pullman, 1965) and the editors’ advice we continue to give dates based on τ 1/2 = 5568 years. For converting dates to A.D./B.C. scale, 1950 has been used as reference year. Ninety-five per cent activity of N.B.S. oxalic acid has been used as modern standard.

The University of Tokyo Carbon Dating Laboratory was established to meet the requirements for dating materials from various fields of science at the university. Installation and testing of the apparatus as well as routine assays have been carried out with counsel of Dr. Nobufusa Saito, Professor of Chemistry, and Dr. Yozo Nogami, Professor of Physics, the University of Tokyo. Management of the laboratory is undertaken by the Carbon Dating Committee of he University of Tokyo. The laboratory has actually been working for a year. This article reports the radiocarbon age measurements made from September 1966 to July 1967, together with a brief description of the measuring system.

This laboratory is now a part of the Bureau of Economic Geology, The University of Texas at Austin. The present list reports C14 measurements made in dating projects completed in the year ending November, 1967, and some measurements for projects still in progress. Age calculations are based on C14 half-life of 5568 yr and a modern standard of 95% of NBS oxalic acid. The deviations reported are based on the counting statistics of the sample, background, and modern, and are ± 1σ except that when the sample count approaches either the modern or the background, 2σ limits are reported. The laboratory continues to use liquid scintillation counting of benzene, using Li2C2 and vanadium activated catalyst in preparation, as described in Texas IV and earlier lists. Chemical yields now average 85%.

Rightmire's caliche dating (done for an M.A. thesis in the Dept. of Geol.) is the principal project reported in this list; in addition to the research he prepared the samples in our laboratory and wrote the statements which accompany the list. Valastro is in charge of all technical operations in the laboratory, and he and Davis share the administrative responsibilities. Davis, who handles sample screening (with the aid of an Advisory Committee) and archaeological appraisal, compiled the list.

The measurements reported were made during the 2nd half of 1967 in the Isotope Lab. of the Inst. of Geophysics and Planetary Physics as a continuation of the UCLA date lists I through VII. Samples were analyzed as CO2-gas at close to one atm in a 7.5 L proportional counter with 3 energy channels described earlier. Radiocarbon ages were calculated for uniformity on the basis of a 5568 yr half-life as was recommended by the Sixth International C14 and H3 Dating Conference, June 1965, in Pullman, Washington. The standard for the contemporary biosphere remains as 95% of the count rate of NBS oxalic acid for radiocarbon labs. Background determinations have been based on CO2 obtained from marble. The error listed is always at least a 1σ statistical counting error. In critical cases C13/C12 isotope ratio measurements were made to correct the dates for fractionation. All samples were subjected to accepted NaOH and/or HCl pretreatments depending on the individual case as a minimum to exclude contamination.

The measurements reported have been carried out during the first half of 1967 in the Isotope Laboratory of the Institute of Geophysics and Planetary Physics as a continuation of the UCLA date lists I through VI. Samples were analyzed as CO2-gas at close to one atm in a 7.5 L proportional counter with 3 energy channels described earlier. Radiocarbon ages have been calculated for uniformity on the basis of a 5568-yr half-life as was recommended by the Sixth International C14 and H3 Dating Conference, June 1965, in Pullman, Washington. The standard for the contemporary biosphere remains as 95% of the count rate of NBS oxalic acid for radiocarbon laboratories. Background determinations have been based on CO2 obtained from marble. The error listed is always at least a 1σ statistical counting error. In critical cases C13/C12 isotope ratio measurements were made to correct the dates for fractionation. All samples were subjected to accepted NaOH and/or HCl pretreatments depending on the individual case as a minimum to exclude contamination. The annual curve for the atmospheric C14 content at China Lake, California, will be published in the next date list.

Radiocarbon dates obtained at the University of Wisconsin since November, 1966, are summarized in this report. The procedures followed and equipment used have been described previously (Wisconsin II).

We used the scintillation variant of the radiocarbon method. The scintillator is prepared on the basis of ethylbenzol [benzene], synthesized from acetylene according to the method of Kuchkarev and Kondratenko (1955). For radiocarbon dating we used materials both rich in carbon: wood and charcoal, and [those] poorer: also peat, buried soils, and fossil bones. In the first instance, the initial material for synthesis was [char] coal, which was treated as follows:

Charcoal. Pavlov campsite [48° 50′ N Lat, 16° 25′ E Long], Czechoslovakia. Archaeologic [sic] age is beginning of Wörm III. Other determinations of charcoal from same campsite are: 24,800 ± 150 yr (GRO-1325, de Vries, 1958) and 26,400 ± 230 yr (GRO-1242, ibid.), which agree with our date. Subm. by A. N. Rogachev; [no date given (E.M.S.)].

Charcoal from campsite hearth from Zozov village, Rovno Oblast [Rovno city: 50° 30′ N Lat, 26° 12′ E Long], Ukrainian SSR. Kut hamlet, semi-subterranean Dwellings VII and VIII. Corded pottery culture; (cf. Gimbutas, 1956 [D.B.S.]). Subm, by I. K. Sveshnikov, Inst. of Social Studies, L'vov.

Lime (grouting) from old structures near city of Khar'khov [50° 00′ N Lat, 36° 10′ E Long]. Subm. [n.d.] by L. P. Papkova.

For determining age scintillation variant was used. Measurement of a large quantity of benzol [benzene] permitted reaching a limit of 62,000 yr without isotope enrichment. Precautions against contamination of the samples with contemporary carbon and tritium were taken in laboratory handling. Dating began only after it had been established that contamination had not taken place during chemical treatment. Benzol which displayed no radioactivity was synthesized from anthracite. Special measures were taken to remove humic acids from the sample by boiling the powdered sample for three days with three fresh lots of 2% solution of NaOH (Arslanov et al., 1966a, p. 134).

Peat, at depth 3.5 m, from upper of 2 layers, at village of Timoshkovichi [53° 35′ N Lat, 26° 05° E Long], Korelichi Raion, Grodno Oblast, Belorussian SSR. Timoshkovichi is located on Novogrudok upland, beyond limits of region of Valday [Wurm] Glaciation. Cross section synchronous with ancient ravine of Neman R. basin where 2 horizons of peat can be detected: the lower, according to pollen data, accumulated at time of Mikulino [Eem] Interglacial; the upper believed accumulated at time of 2nd climatic optimum of Mikulino Interglacial, or at time of early Interstadial of Valday [Wurm] Glaciation (Tsapenko and Makhnach, 1959). Coll. 1962 by N. S. Chebotareva, Geog. Inst., Acad. of Sci., USSR.

Charcoal from layer of buried soil from old brick works in Mende, Hungary (47° 30′ N Lat, 19° 30′ E Long) [unconfirmed, D.B.S.]. Deposits are humic loess loams, containing bits of charcoal. Sample at depth ca. 6.5 m. This cross section is one of classical loess excavations in Hungary. Sample coll. 1964, by M. Pechi [Pees] and D. Khan [Hahn].

Charcoal from Uplistsikhe village [unlocated], Katlanis Khevi. Archaeologic date: late Bronze age, 12th to 7th centuries B.C. Subm. [n.d.] by D. Khakhutashvili.