HARDWICKE'S SCIENCE-GOSSIP. 



125 



which I am unable to name, and shall be glad if any 



of your readers can assist me. Fig. 67, side view ; 



Fig. 68, dorsal view. I have never seen more than 



a very limited number of them, and these always 



from one locality, a shaded well, having a north. 



west aspect. Above, and along the surface of the 



water, the stones are covered with mosses and 



diatoms, and Batrachiospernmm moniliforme is very 



plentiful. I get there several rotifers, and among 



them, very sparingly, my unknown specimen. Its 



lorica is cylindrical, slightly compressed, open on the 



ventral side, and with faint indications of a dorsal 



ridge anteriorly. On the dorsal view, it is pointed 



anteriorly, rapidly widening to about the middle, 



then narrowing posteriorly, which is terminated by 



two spines, curving upwards and outwards. I have 



only been able to detect one eye. The gizzard or 



masticatory organ is very difficult to make out, from 



the rotund conformation of the animal. Rotatory 



organ with two superior hooks, and two inferior 



large cilia, or, perhaps, the latter may be designated 



setae. Tail-foot, forked ; toes about as long as the 



foot. If new, which perhaps is hardly probable, 



I propose to call it Cohcrus navicularis, a name 



expressive of its general resemblance, on its dorsal 



aspect, to a ship or boat. On a subsequent occasion, 



I may invite the assistance of brother naturalists in 



naming others of the free-swimming rotiferae. 



J. E. Lord. 

 Raivtenstall, near Manchester. 



GOSSIP ON CURRENT TOPICS. 

 By W, Mattieu Williams, F.R.A.S. 



THE Society of Arts is gradually developing into 

 a practical science parliament where all kinds 

 of scientific novelties that have reached the stage of 

 useful application may be brought forward by their 

 inventors and publicly discussed, criticised with any 

 degree of courteous severity by those who either object 

 to them on scientific grounds, or who have oppos- 

 ing interests. This is very desirable, and hitherto 

 the debates have been characterised by an amount of 

 straightforward and concise adherence to the subject 

 on hand that contrasts very favourably with some 

 recent debates in " another place." 



One of the longest and most animated of these 

 followed (with adjournments) the paper read by Dr. 

 Percy Frankland (son of Professor Frankland) on 

 March 13th. The question raised is one of much 

 moment, viz. whether the water of a river, such as 

 the Thames, when once polluted by sewage can be 

 rendered fit for drinking purposes, either by the 

 oxidation incident to its own flow, or by artificial 

 filtration. Dr. Frankland contended that it cannot, 

 and therefore that the Thames' supplies to London 

 should be abandoned ; while many eminent engi- 

 neers and a few chemists very positively contradicted 



both his data and his conclusions. It should be 

 understood that most of these are concerned in the 

 construction of filter beds and other engineering 

 appliances and processes for river-water purification, 

 or in schemes for chemical precipitation. It is quite 

 right, of course, where such large interests are con- 

 cerned, that full opportunities for defence should be 

 afforded against an attack upon those interests. Dr. 

 Frankland's paper certainly is such an attack, and 

 a very serious one, as we cannot submit to be 

 poisoned merely for the sake of maintaining the value 

 of water companies' shares. The advocates of river 

 supply make out a fair case so long as the drainage 

 areas of the upper waters are free from epidemics, but 

 whether or not the specific microzoa producing such 

 diseases as cholera and typhoid fever can be oxidized 

 to death, or kept back by filter beds, or exterminated 

 by A. B. C. or other processes, still seems doubtful. 

 Those of our readers who are interested in the subject 

 should not fail to read the paper and the discussion 

 which are fully reported in the society's journal. 

 Some very caustic comments on the paper are 

 published in the Journal of Science for May, under 

 the title of " The Ghost of the Season." The writer 

 pleads for the A. B. C. process. 



The interesting pictorial and mechanical display 

 made by the water companies at the Health Exhibi- 

 tion is another form of reply, though not directly put 

 forward as such. The pretty pictures of the ' ' shining 

 river " do not, however, display the underground 

 tributaries. But to be very critical on the water 

 companies just now, is like hitting a man when he 

 is down. 



■ Apropos oi typhoid and cholera microzoa, we see that 

 Dr. B. W. Richardson is sounding a note of warning, 

 not the usual note of warning against invasion by these 

 creatures, but against the tendency to ignore " all the 

 preceding clinical history," and treat it " as nothing 

 in presence of bacillus." The subject is treated in 

 his usual quaint and picturesque style in the May 

 number of his ' ' Asclepiad." He asks : ' ' Can this 

 greedily absorbed hypothesis come to any good ? 

 Upon the evidence of how many or how few men 

 does it rest ? On what reasoning does it rest ? Who 

 has separated, in relation to it, coincidence from 

 causation ? " Whether " we have either before us a 

 revolution in discovery, momentous in character, or 

 one of the most dangerous of speculations that was 

 ever revived out of the mad past — Dwight's animal- 

 cular hypothesis with less excuse for it," it is certainly 

 desirable that some protest or scepticism should be 

 agitated against the risk we encounter from the 

 natural tendency of medical aspirants to perpetrate 

 fashionable follies in their desire to be well up to the 

 level of latest discoveries, andthe most advanced prac- 

 tice ; to follow, in short, the medical fashion of the day. 

 The observations of Dr. Henry F. Walker, of New 

 York, concerning the absence of earth-worms in 

 regions where man has not settled are very curious. 



