64 



NATURE 



{Nov. 27, 187^ 



controversies which arose out of his laryngoscopic work), 

 was rendering him unfitted for the energetic performance 

 of his professorinl duties, he withdrew to Leipzig, where 

 he was made Honorary Professor at the University, and 

 where he continued to reside until his death, on Sept. 16 

 in the present year. 



Carried off while yet in the prime of his life, and 

 the energies of his last few years impaired by an 

 insidious disease, Czermak has perhaps left a mark on 

 the scientific progress of his time incommensurate with 

 his talents or his promise. He will doubtless be best re- 

 membered through his laryngoscopic labours. We owe 

 to him the real introduction into medical practice of this 

 valuable instrument. But his other researches, such as 

 those on the action of the vagus, the pulse, the sense of 

 touch, the manage movements resulting from injuries to 

 the brain, those on dyspncea, and others, show remarkable 

 acuteness and clearness of insight. 



Two talents he possessed deserve special notice. He 

 had remarkable aptitude in devising apparatus for ob- 

 serving or for demonstrating physiological phenomena. 

 It was this faculty which made him successful where 

 others had failed in the use of the laryngeal mirror ; and 

 would be difficult to exaggerate the immense help to 

 experimental physiology which has been afforded by the 

 ingenious '" holder" which bears his name. 



The other faculty, that of popular exposition, less com- 

 mon in his country than in ours, he possessed to a very 

 high degree. And his popular lectures, which were origi- 

 nally deHvered at Jena, and which were reviewed in an 

 early number of NATURE, achieved and deserved great 

 popularity. 



Perhaps had his love of teaching been less strong, his 

 work as an investigator would have been more sustained 

 and weighty. But while in this country we might with 

 profit often lose a lecturer and gain an investigator, Ger- 

 many could well aflbrd that one whose powers of rigorous 

 and yet clear and popular demonstration were so excep- 

 tionally great, should somewhat sUcken in his work as an 

 inquirer. Or perhaps we should not so much say that 

 Czermak slackened m inquiry, as that the consciousness 

 of his power as an expositor, and the delight he conse- 

 quently took in exposition, drew much of his energy in 

 that direction. In the grounds of his residence at Leip- 

 zig he had built and fitted, at his own expense, a large 

 hall, or " spcctatorium," as he called it, in which he pro- 

 posed to deliver lectures on physiology, richly illustrated 

 with experiments. In connection with the hall, the con- 

 struction of which was admirably adapted in every way 

 for its purpose, he had also erected a private laboratory 

 for research ; and on both he had spent much time and 

 labour. They were intended to be a supplement — not a 

 rival — to the more technical institute of Prof Ludwig in 

 the same city. The writer will never forget the delight 

 with which Czermak showed this " Erklarungs-Tempel," 

 — as he was fond of calling it — to Dr. Sharpey and him- 

 self in the summer of 1871, and pointed out all its in- 

 genious contrivances, and the enthusiasm with which he 

 looked forward to the lectures which would be delivered, 

 and the work whicli would be carried on in it. He lived 

 to open it by an inaugural lecture in December 1872 ; but 

 the effects of his fatal disease were already painfully evi- 

 dent ; and after a vain struggle during the following 

 summer, Czermak — just as the British Association v/as 

 gathering for its meeting at Bradford — was taken away 

 Irom his unfinished work. He was a man of broad cul- 

 ture, outside his professional attainments. In philosophy 

 especially he was well versed ; and his last contribution 

 to scientific literature — a pap r in " Pfliiger's Archiv," on 

 the mesmerism of animals — was doubilcss prompted by 

 his interest in psychological questions. His straightfor- 

 ward, generous, and unostentatious manner formed a 

 fitting frame for his intellectual attainments. 



A widow and children mourn his death. He is also 



mourned for by many friends in many lands, both by those 

 who had known him long and by those who knew him 

 for a short while only. M. FOSTER 



THE ATMOSPHERIC TELEGRAPH 



"T^HE T'/we'j- of the 15th inst. contained an article on the 

 ■*■ Pneumatic Despatch, which has never been used to 

 any extent in this country. From that article we learn the 

 following particulars as to the working of this method of 

 conveyance in London : — 



The pneumatic tube extends from the London and 

 North-Western Railway Station at Euston Square to the 

 General Post Office in St. Martin's-le-Grand. The central 

 station is in Holborn, where is also the machinery for 

 effecting the transit of the trains. Here the tube is 

 divided, so that in effect there are two tubes opening into 

 the station, one from Euston to Holborn, and the other 

 from the Post Office. The length of the tube between 

 Holborn and Euston is 3,oSo yards, or exactly a mile and 

 three-quarters, a greater length than was originally con- 

 templated, but which was rendered necessary by the 

 avoidance of certain property on the route. The 

 tube is of a flattened horse-shoe section 5 ft. wide and 

 4 ft. 6 in. high at the centre, having a sectional area of 17 

 square feet. The straight portions of the line are formed 

 of a continuous cast-iron tube, the curved lengths being 

 constructed in brickwork, with a facing of cement. The 

 gradients are easy ; the two chief are i in 45 and i in 60, 

 some portions of the line being on the level ; the sharpest 

 curve is that near the Holborn station, which is 70 ft. 

 radius. The tube between Holborn and the Post Office 

 is 1,658 yards in length, or 102 yards less than a mile, 

 and is of the same section, and similarly constructed to 

 the first length. Two gradients of i in 15 occur on the 

 Post Office section, but this steep inclination is in noway 

 inimical to the working of the system. The Holborn 

 station is situated at right angles to the line of the tubes, 

 which are therefore turned towards the station into which 

 each opens. All through trains, therefore, have to re- 

 verse there, and this is effected in a very simple manner 

 by a self-acting arrangement. A train upon its arrival 

 runs by virtue of its acquired momentum up a short in- 

 cline, at the summit of which it momentarily stops, and 

 then quickly descends by gravity. In its descent it is 

 turned on to a pair of rails leading to the other tube, into 

 which it enters and through v/hich it continues its jour- 

 ney, the whole process of reversing occupying barely 30 

 seconds. Trains containing goods for the Holborn 

 station are simply run down from the top of the incline 

 on to a siding. 



The vv.aggon5, or carriers, as they are termed, weigh 

 22cwt., are 10 ft. 4 in. in length, and have a transverse 

 contour conforming to that of the tube. They are, how- 

 ever, of a slightly smaller area than the tube itself, the 

 difierence — about an inch all round — being occupied by 

 a flange of indiarubber, which causes the carrier to fit the 

 tube exactly, and so to form a piston upon which the air 

 acts. The machinery for propelling the carriers consists 

 of a steam engine having a pair of 24-in cylinders with 

 20 in. stroke. This engine drives a fan 22 ft. 6 in. in dia- 

 meter, and the two are geared together in such a manner 

 th.at one revolution of the former gives two of the latter, 

 or, in technical terms, the engine is geared at 2 to i with 

 the fan. The trains are drawn from Euston and the Post 

 Office by exhaustion, and are propelled to those points by 

 pressure The working of the fan, however, is riot re- 

 versed to suit these constantly varying conditions ; it 

 works continuously, the alternate action of pressure and 

 exhaustion being governed by valves. The engine takes 

 steam from three Cornish boilers, each 30 ft. long and 

 6 ft. 6 in. in diameter, Telegraphic signalling is carried on 

 between the three stations by means of needle instru- 

 ments. 



