476 



NATURE 



[March i6, 1893 



been expended for pure research in anthropology under one 

 direction as during the past year ; and praise and honour are 

 due to the business men forming the directory of the Exposition 

 in Chicago, who have so cordially met my proposals and fur- 

 nished the means for carrying them out on so grand a scale. 

 Notwithstanding the vast material interests involved in the 

 Columbian Exposition, it must be admitted that Chicago has 

 nobly supported pure science in this connection and has shown 

 an appreciation of its high aims. 



On the Honduras Expedition Prof. Putnam reports as 

 follows : — 



It was stated in the last report that an expedition had just 

 started to make the preliminary explorations for the ancient 

 ruins of Copan, and in that report is given a brief outline of the 

 origin and plans of this undertaking on the part of the Museum 

 to be carried on by the assistance of patrons of archaeological 

 research. It is indeed a pleasurable duty to announce that the 

 first season's work of the expedition has proved a decided 

 success ; and that although the party had many trials and 

 difficulties to overcome, no serious accidents or sickness occurred. 

 Messrs. Saville and Owens returned in safety, in May last, 

 bringing with them a large number of most interesting and 

 important objects illustrating the wonderful carvings in stone ; 

 several vessels and many fragments of pottery ; numerous 

 ornaments made of stone, shells and bone ; stone implements ; 

 and portions of human skeletons. Among the latter are several 

 incisor teeth, each of which contains a small piece of green 

 stone, presumbly jadeite, set in a cavity drilled on the front 

 surface of the tooth. We had before received from very ancient 

 graves in Yucatan human teeth filed in a peculiar manner, and 

 now we have teeth from the ancient graves in Copan ornamented 

 in another way. This is of particular interest in adding one 

 more to the several facts pointing to Asiatic arts and customs as 

 the origin of those of the early peoples of Central America. A 

 most striking resemblance to Asiatic art is noticed in several of 

 the heads carved in stone, — one in particular, if seen in any 

 collection and not labelled as to its origin, would probably pass 

 almost unchallenged as from Southern Asia. These may prove 

 to be simply coincidences of expression of peoples of correspond- 

 ing mental development brought about by corresponding natural 

 surroundings and conditions. At present we must admit that 

 there are many resemblances in architecture, sculpture, ornament, 

 and religious symbolism, between Central America and portions 

 of Asia. The true meaning of these resemblances will be made 

 known as authentic materials for study are obtained by such 

 thorough and exhaustive field work as the Museum has been 

 carrying on ; and none is so important for this special subject as 

 that of the Honduras expedition. For this work, however, a 

 large sum of money is required. The ten years allowed for the 

 work in Honduras by the edict of that government must be 

 utilised to the fullest extent ; and each year must find the 

 Museum ready to put its party in the field well equipped and 

 provided with money for the very expensive work to be per- 

 formed. 



It is not my intention to give an abstract of the results of last 

 year's explorations at Copan. It is far better that the report 

 should be carefully prepared by those engaged in the actual 

 field work from year to year. After sufficient information has 

 been obtained about the ruins themselves, and the architectural 

 and chronological relationship of the various structures ; and 

 after a thorough knowledge of the different modes of burial has 

 been acquired, and all possible objects have been collected, then 

 conclusions can be drawn which will be of scientific value, since 

 they will be based on a thorough knowledge of all the facts. An 

 important beginning was made by the expedition last year, plans 

 of the plaza and of the principal structures forming the great 

 mass of the ruins having been made, many photographs taken, 

 and paper moulds of important sculptures, lines of hieroglyphs 

 and several of the large idols or carved monoliths secured. Con- 

 sidering the difficulties of transportation (wholly by mules to the 

 coast — a seven days' journey), both Messrs. Saville and Owens, 

 •ind all associated with them must be congratulated on what they 

 accomplished. Since the return of the expedition the photo- 

 graphs have been printed, preliminary reports have been pre- 

 pared, and casts have been made from the moulds. These casts 

 are now being placed in the Museum, and a series has also been 

 made for the Boston Art Museum, and another for the 

 Columbian Exposition. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Cambridge. — Prof. Liveing announces a course of demonstra- 

 tions in spectroscopic chemistry, to be given during the first 

 three weeks of the Easter term, daily (except on Saturdays) at 

 II, beginning on April 24. 



The examination in Sanitary Science for the Diploma in 

 Public Health will be held from April 4 to April 8. 



The honorary degree of Doctor in Science will be conferred 

 on Prof. Virchow, at a special congregation on Tuesday, 

 March 21. 



A grant of ;^65 has been made from the Worts Travelling 

 Scholars' Fund to H. Woods, of St. John's College, for the 

 purpose of palaeontological research in Saxony and Bohemia. 



Lawrence Crawford, B.A., Fifth Wrangler, 1890, has been 

 elected to a Fellowship at King's College. 



SOCIETIES AND ACADEMIES. 

 London. 



Royal Society, February 16.— "The Value of the 

 Mechanical Equivalent of Heat, deduced from some Experi- 

 ments performed with the view of establishing the Relation 

 between the Electrical and Mechanical Units, together with an 

 Investigation into the Capacity for Heat of Water at different 

 Temperatures." By E. H. Griffiths, M.A., Assistant Lecturer, 

 Sidney Sussex College, Cambridge, assisted by G. M. Clark, 

 B.A., Sidney Sussex College, Cambridge. Communicated 

 by R. T. Glazebrook, F.R.S. 



If a calorimeter is suspended in a chamber, the walls of which 

 are maintained at a constant temperature, we can, by observa- 

 tions over a small range across that outside temperature, deduce 

 the rate of rise due to the mechanical work done in the calori- 

 meter, when the supply of heat is derived from stirring only. 

 By repeating the observations in a similar manner over ranges 

 whose mean temperature Q^ differs from that of the surrounding 

 walls ^0, we obtain the change in temperature due to the com- 

 bined effects of the stirring, radiation, conduction, and convec- 

 tion at all points of our whole range of temperature. As the 

 success of the method depends (i) on the possibility of main- 

 taining the exterior temperature unchanged, and (2) on the 

 regularity of the supply of heat due to the stirring, we briefly 

 indicate our method of securing those conditions. 



1. The calorimeter 1 was suspended within an air-tight steel 

 chamber. The walls and floor of this chamber were double, 

 and the space between them filled with mercury. The whole 

 structure was placed in a tank containing about 20 gallons of 

 water, and was supported in such a manner that there were 

 about 3 inches of water both above and beneath it. The 

 mercury was connected by a tube with a gas regulator of a novel 

 form, which controlled the supply of gas to a large number of 

 jets. Above those jets was placed a flat silver tube, through 

 which tap water was continually flowing into the tank, all parts 

 of which were maintained at an equal temperature by the rapid 

 rotation of a large screw. Thus, the calorimeter may be re- 

 garded as suspended within a chamber placed in the bulb of 

 a huge thermometer — the mercury in that bulb weighing 70 lbs. 

 A change of i°C. in the temperature of the tank water caused 

 the mercury in the tubes of the regulating apparatus to rise about 

 300 mm. Special arrangements were made by which it was 

 possible to set the apparatus so that the walls surrounding the 

 calorimeter could be maintained for any length of time at any 

 required temperature, from that of the tap water (in summer 

 about 13° C. in winter 3° C.) up to 40° C. or 50° C. We know 

 by observation that the temperature of the steel chamber (when 

 once adjusted) did not vary by 1/500° C, and we believe the 

 variations were much less. 



2. We experienced great difficulty in devising a suitable form 

 of stirrer ; and we attribute the failure of our earlier experiments 

 to defects in the ordinary forms. We find it impossible, with- 

 out a lengthy description, to give a clear idea of the stirrer ulti- 

 mately adopted. We can only state here that it was completely 

 immersed when the depth of the water exceeded i cm., that 



1 The calorimeter was of cylindrical form, and suspended by three glass 

 tubes. It was made of "gilding metal," which both internally and ex- 

 ternally was covered with a considerable thickness of gold. All metal 

 surfaces within the calorimeter were thickly gilded. 



NO. 1220, VOL. 47] 



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