Feo. ly, 1881] 



NATURE 



zn 



quantity of either of these substances, placed in a bulb a cubic 

 inch in volume, warmed, and exposed to the intermittent beam, 

 emits a sound of extraordinary power. 



I also tried to extract sounds from perfumes, which I had 

 proved in 1861 to be ab-;orbers of radiant heat. I limit myself 

 here to the vapours of pachouli and cassia, the former exercising 

 a measured absorption of 30, and the latter an absorption of 109. 

 Placed in dried flasks, and slightly warmed, sounds were obtaiued 

 from both these substances, but the sound of cassia was much 

 louder than that of pachouli. 



Many years ago I had proved tetrachloride of carbon to be 

 highly diathermanous. Its sounding power is as feeble as its 

 absorbent power. 



In I'elation to colliery explosions, the deportment of marsh-gas 

 was of special interest. Prof. Dewar was good enough to 

 furnish me with a pure sample of this gas. The sounds pro- 

 duced by it, when exposed to the intermittent beam, were very 

 powerful. 



Chloride of methyl, a liquid which boils at the ordinary tem- 

 perature of the air, was poured into a small flask, and permitted 

 to displace the air within it. Exposed to the intermittent beam, 

 its sound was similar in power to that of marsh-gas. 



The specific gravity of marsh-gas being about half that of air, 

 it might be expected that the flask containing it, when left open 

 and erect, would soon get rid of its contents. This however is 

 not the case. After a considerable interval the film of this gas 

 clinging to the interior surface of the flask was able to pro- 

 duce Sounds of great power. 



A small quantity of liquid bromine being poured into a well- 

 dried flask, the brown vapour rapidly diffused itself in the air 

 above the liquid. Placed in the intermittent beaai, a somewhat 

 forcible sound was produced. This might seem to militate 

 against my former experiments, which assigned a very low ab- 

 sorptive power to bromine vapour. But my former experiments 

 on this vapour were conducted with obscure heat ; whereas in 

 the present instance I had to deal with the r.idiation from 

 incandescent lime, whose heat is in part luminous. Now the 

 colour of the bromme vapour proves it to be an energetic 

 absorber of the luminous rays ; and to them, when suddenly 

 converted into thermometric heat in the body of the vapour, I 

 thought the sounds might be due. 



BetMeen the flask containing the bromine and the rotating disk 

 I theref jre placed an empty glass cell : the sounds continued. 

 I then filled the cell with transparent bisulphide of carbon : the 

 sounds still continued. For the transparent bisulphide I then 

 substituted the same liquid saturated with dissolved iodine. This 

 solution cut off" the light, while allowing the rays of heat free 

 transmission : the sounds w ere immediately stilled. 



Iodine vaporised by heat in a small flask yielded a forcible 

 sound, which was not sensibly affected by the interposition of 

 transparent bisulphide of carbon, but which was completely 

 quelled by the iodine solution. It might indeed have been fore- 

 seen that the rays transmitted by the iodine as a liquid would 

 also be transmitted by its vapour, and thus fail to be converted 

 into sound.' 



To complete the argurcent : — While the flask containing the 

 bromine vapour was sounding in the intermittent beam, a strong 

 solution of alum was interposed between it and the rotating disk. 

 There was no sensible abatement of the sounds with either 

 bromine or iodine vapour. 



In these experiments the rays from the lime-light were con- 

 verged to a point a little beyond the rotating disk. In the next 

 experiment they were rendered parallel by the mirror, and 

 afterwards rendered convergent by a lens of ice. At the focus 

 of the ice-lens the sounds were extracted from both bromine and 

 iodine vapour. Sounds were also produced after the beam 

 had been sent through the alum solution and the ice-lens con- 

 jointly. 



With a very rude arrangement I have been able to hear the 

 sounds of the more active vapours at a distance of 100 feet from 

 the source of rays. 



Several vapours other than those mentioned in this abstract 

 have been examined, and sounds obtained from all of them. 

 The vapours of all compound liquids will, I doubt not, be found 

 sonorous in the intermittent beam. And, as I question whether 

 there is an absolutely diathennatious substance in nature, I think it 

 probable thvt even the vapours of elementary bodies, including 

 the elementary gases, when more strictly examined, will be found 

 capable of producing sounds. 



* I intentionally use this phraseology. 



INTERESTING NEW CRINOIDS 



TN the Mlemoiys of the Swiss Pal.-eontological Society for 1S80 

 -*■ Prof. P. de Loriol has recently described a remarkable new 

 Crinoid which he refers to the little known genus Tliiollieria-iiins, 

 Etallon, under the name of T. ribeiroi. It occurs in the U]>per 

 Jurassic beds of Engenheiro, in Portugal. The calyx, like that 

 of most Jurassic Comatultc, has five small prismatic basals 

 attached to the under surface of the radials. But the centro- 

 dorsal piece on which the calyx rests is not entirely separated 

 from the louer part of the stem, as is the case in the Comatula, 

 though it resembles that of a Comatula in bearing cirrhi. 



ThiolUerkrinus was a stalked Crinoid that never developed 

 beyond the stage at which cirrhi appear on the enlarged upper- 

 most stem-ji.int of the stalked larva of Ccmafula. The under- 

 face of the centrodorsal and the terminal faces of the other 

 >tem-joints resemble those of the Comatula larva and also of 

 Bourgucticrinns and Rhizocrinus in their oval shape and in the 

 presence of transverse ridges which are in different planes at the 

 two ends of each joint. ThiolUerkrinus therefore is a permanent 

 larval form, and furnishes an intermediate stage between the 

 stalked i?m«y«i'/;Vr/H;w and the free Comatula. The top stem- 

 joint of the former bears no cirrhi, as it does in ThiolUcricriuus 

 and in Comatula ; while in the latter it develops cirrhi, and 

 unites closely with the calyx, separating from the rest of the 

 larval stem on which it ws previously fixed. 



Another form of considerable morphological interest, from its 

 occupying an intermediate position between two well-defined 

 genera, has been lately described by Mr. P. H. Carpenter under 

 the name of Mt-sxritms. The stem-joints are of the type already 

 mentioned as characteristic of Bourgucticrinus, having oval faces 

 marked by transverse ridges in different planes. But the upper 

 stem-joint is not enlarged as it is in Bourgucticrinus and in the 

 Apiocriniilic generally, while the form of the calyx recalls that of 

 the Pentacrinidiv. It consists of five radials with well-developed 

 articular faces, resting on five basals which form a complete ring 

 as in the recent Pcntacrinus Wyvillc- T/iomsoni, from 800 fathoms 

 in the Atlantic off" the coast of Portugal. 



Broadly speakin'.r, therefore, Mesocrinns combines the stem of 

 BourgiieticriiiHS with the calyx of Pentacrinus, or rather of 

 Cainoeriiius, as Prof, de Loriol prefers to call that section of the 

 Pentacrimis type in which the basal ring is closed. Mesocrinus 

 is an Upper Cretaceous genus, one species occurring in the 

 "Planerkalk" of Streben in Saxony, while another and larger 

 one was found in the "Mucronaten Kreide" of Southern 

 Sweden. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE 



Oxford. — In consequence of the unsatisfactory state of many 

 of the lodi;ing-houses in Oxford, in respect of their sanitary 

 arrangements, a proposal will be brought before Congregation 

 on March I "to make better provision for the supervision of 

 lodging-hcnises." One of the delegates for licensing lodgings 

 will be stipendiary, and it will be his duty to inspect every 

 dwelling-house proposed for this use and to satisfy himself of its 

 sanitary fitness. He shall have the assistance of a sanitary 

 inspector, and shall have proctorial authority over members of 

 the University in his character of inspector. 



A special statute will also be proposed authorising the present 

 delegates of lodging-houses to spend whatever sum they may 

 think necessary on a general inspection of lodging-houses 

 during the present year. 



There will be holden at Christ Church on Saturday, March 

 12, an election to at least one Mathematical Junior Studentship, 

 and at least one in Natural Science, tenable for five years from 

 the day uf election. They will be of the annual value either (i) 

 of 100/, (including an allowance for room rent) if the Governing 

 Body .shall so determine ; or (2) of 85/. (also including an allow- 

 ance for room rent), which may be raised to the larger sum above 

 named after the completion of one year's residence, if the 

 Governing Body shall so determine. Candidates for the Mathe- 

 matical Studentships and candidates for the Natural Science 

 Studentships who offer mathematics will call upon the Dean on 

 Monday, February 28, between 12,30 and 1.30 p.m. ; candi- 

 dates for the Natural .Science Studentships who do not offer 

 mathematics, on March 2, between 12.30 and 1.30 p.m. All 

 must produce certificates both of the day of their birth and of 

 good character. The examinations will follow in each case at 



