May 4, 1893] 



NATURE 



2 ( 



by the apparent motion of the sun, and he considers that it 

 is the lateral pressure that causes the barometer to rise to a 

 maximum about half way between local sunrise and local 

 maximum of temperature. He states that an advancing area, 

 which is increasing in the temperature of its lower strata, 

 will cause a high barometer area at a considerable distance in 

 front of itself, and that the reverse occurs during the advance 

 of an area which is diminishing in the temperature of its lower 

 strata. The evening maximum he takes to be a reactionary 

 wave from the afternoon minimum. — Recent foreign studies of 

 thunderstorms, by R. de C. Ward. The author has collected 

 the literature of the subject from the time that Mr. G. J. 

 Symons commenced his observations, in 1856, down to the close 

 of 1892, and gives a general summary of the results of each 

 discussion. The present paper refers entirely to Great Britain. 

 — The Chinook wind, by H. M. Ballou. Comparatively little 

 has yet been written about the Chinook wind ; its name is 

 derived from that of the tribe of Chinook Indians living near 

 Puget's Sound. During the prevalence of the wind the ther- 

 mometer often rises from below zero to 40° or 45° in a few hours. 

 It is analogous to the Fohn in Switzerland, and similar winds 

 are reported from various parts of the world. All that is 

 needed to produce them are high and low pressure areas, whereby 

 the air is caused to pass over the mountains, depositing its mois- 

 ture during the ascent, and descending on the leeward side. 

 The author gives a list of works bearing upon the subject. — 

 The North Atlantic hurricane of December 22, 1892, by E. 

 Hayden. The paper is accompanied by a map showing the 

 great site and severity of the storm. It is estimated that the 

 area embraced was fully four million square miles, and the 

 author considers that this storm is accountable in some 

 degree for the subsequent very cold weather in North America 

 and Europe. 



SOCIETIES AND ACADEMIES. 



London. 

 Royal Society, February 9. — "Preliminary Account of 

 the Arrangement of the Sympathetic Nervous System, based 

 chiefly on Observations upon Pilomotor Nerves." I. By J. N. 

 Langley, F.R.S., Fellow of Trinity College, Cambridge. In the 

 cat, the spinal nerves which contain pilo-motor fibres in their 

 nerve-roots, are usually the 4th thoracic to the 3rd lumbar inclu- 

 sive. The spinal pilo-motor fibres run into the sympathetic trunk, 

 there they become connected with nerve-cells; on leavingthe sym- 

 pathetic chain, they run to their peripheral endings in cranial or 

 spinal nerves. The fibres to the body accompany those dorsal 

 cutaneous branches of the spinal nerves, which supply the skin 

 over and close to the vertebras. Broadly speaking, the pilo- 

 motor fibres run from the sympathetic chain to the cranial and 

 spinal nerves in the grey rami, but a few fibres may run out in 

 the white rami. Broadly speaking, the fibres issuing from any 

 one ganglion are connected with nerve-cells in that ganglion 

 and with no other sympathetic nerve-cell. In some cases a cer- 

 tain number of such fibres are connected with nerve-cells, not in 

 the ganglion from which they issue, but in the ganglion imme- 

 diately above or below it. The fibres, before and after they 

 have joined nerve-cells, may be called respectively pre-ganglionic 

 and post-ganglionic. Each ganglion, by its post-ganglionic 

 fibres, supplies, in any one individual, a definite portion of skin. 

 The areas supplied by the ganglia from above downwards, start- 

 ing with the superior cervical ganglion, are, apart from a vari- 

 able amount of overlapping, successive areas. The cranial rami 

 of the superior cervical ganglion supply the skin of the dorsal 

 part of the head, except a posterior portion, beginning about ij 

 cm. behind the anterior level of the ears ; this unaffected region 

 we may call the occipital region. The cervical rami of the 

 superior cervical ganglion supply the skin of the occipital region 

 of the head by fibres running in the great occipital (2nd cervical) 

 nerve, and the skin over the first three or four cervical vertebrae 

 by fibres running in the 3rd cervical nerve. The ganglion stel- 

 latum, by its cervical rami, supplies the skin from the 3rd and 

 4th cervical vertebrae to some point between the spine of the 2nd 

 and 3rd thoracic vertebrae. Often its area extends upwards to 

 join the occipital region. The areas supplied by the post-gang- 

 lionic pilo-motor fibres of the 3rd, 4th, 5th, and 6th cervical 

 nerves vary in relative size in different individuals ; roughly we 

 may take the 3rd nerve as supplying the skin over the first three 



NO. 1227, VOL. 48] 



and a half vertebrae, and the others as supplying successive 

 strips of about two vertebras each. In the fore leg region, one, 

 two, or three spinal nerves send no cutaneous branches to the 

 mid-line of the back. These are the 7th and 8th cervical, and 

 the 1st thoracic, nerves. Sometimes the 7th, sometimes the 

 1st, thoracic has such a cutaneous branch ; corresponding to the 

 presence or absence of these cutaneous branches is the presence 

 or absence of pilo-motor fibres in the rami which pass from the 

 ganglion stellatum to the respective nerves. The ganglion stel- 

 latum also sends pilo-motor fibres to the first four thoracic 

 nerves. From the 5th thoracic nerve downwards (and some- 

 times from the 4th) there is a ganglion and ramus for each 

 nerve. The distribution of all these rami down to the 4th lum- 

 bar may be considered together. The area of the second thoracic 

 ramus (or of the 1st, as mentioned above) follows on the area of 

 the lowest effective cervical ramus. The 4th lumber ramus sup- 

 plies either the skin over the 7th lumbar vertebra and a small 

 piece of sacrum or the skin over the sacrum. Between the limits 

 just given for the 2nd thoracic and the fourth lumbar the areas 

 follow on each other, the length of each area being about that 

 of a vertebra. 



Below the 4th lumbar nerve is the hind leg region, which is 

 like that of the fore leg already mentioned, in so far as one, two, 

 or three nerves have no dorsal cutaneous branches to the mid- 

 line, and the corresponding rami have no pilo-motor fibres. 

 These nerves are the Sth, 6th, and 7th lumbar. 



About the end of the sacrum appears to be the dividing line 

 between the areas of the rami which come from above and those 

 which come from below the ineffective ramus or rami. Thus 

 the skin over the lower part of the sacrum may be supplied by 

 the 4th, 5th, or, perhaps, the 6th lumbar ramus, the skin over 

 the upper coccygeal vertebrse by the 7th lumbar or ist sacral. 

 The second sacral ramus, as a rule, supplies the hairs of the tail 

 just'above the level of the anus and over it ; the 3rd sacral ramus 

 supplies the hairs for about an inch and a half below the level 

 of the anus. The coccygeal ganglion gives off rami to the 

 several coccygeal nerves, and these supply different lengths of 

 the tail. 



It is easily shown that the area of the skin supplied with pilo- 

 motor fibres by the dorsal cutaneous branch of any given spinal 

 nerve is also supplied by it with sensory fibres. And there is 

 good reason for believing that the fibres of the grey ramus of a 

 nerve, i.e. the post-ganglionic sympathetic fibres of a spinal 

 nerve, have in the main the same distribution in the skin as the 

 sensory fibres of the nerve. 



Each spinal nerve, from the ist cervical to the 3rd lumbar, 

 sends fibres to 7 or 8 sympathetic ganglia. For the details of this 

 connection we must refer to the figure appended to the paper. 



March 23. — "On the Variation of Surface Energy with 

 Temperature," by William Ramsay, Ph.D., F.R.S., and John 

 Shields, B.Sc, Ph.D. 



It is shown that a close analogy exists between the equation 

 for gases, 



pv = RT, 



and an equation expressing the relation of surface energy to 

 temperature, 



tS = KT, 



where 7 is surface tension ; s, surface ; k, a constant ; and t, 

 temperature measured downwards from a point about 6° below 

 the critical point of the fluid. As the origin of T in the gaseous 

 equation is where / = o, so the origin of t should be where 

 7 = 0. Correcting the above equation so that t shall represent 

 the number of degrees measured downwards from the critical 

 point, the equation becomes 



7s = K (t - ii). 



But even this equation does not express the whole truth. For 

 at temperatures less than 30° below the critical temperature, the 

 relation between surface energy and temperature is not a recti- 

 linear one ; a correction is therefore introduced in the form of a 

 second term, which becomes insignificant at temperatures more 

 than 25' or 30° t ; it is 



ys = KT- Kii (i - 10"*'). 



The liquids examined were : ether, methyl formate, ethyl 

 acetate, carbon tetrachloride, benzene, chlorobenzene, acetic 

 acid, and methyl and ethyl alcohols ; in fact, the only ones for 

 which data are available. For, in order to calculate 7 from the 

 rise in a capillary tube, it is necessary to know the density of 



