494 



NATURE 



\Sept. 5, 1878 



origin of any other instinct — that of running away from 

 danger included. Moreover, one of the animals to which 

 Preyer refers, viz., the Armadillo vulgaris, not only 

 remains motionless when alarmed, but rolls itself up into 

 a ball — an action which certainly cannot be explained on 

 the hypothesis of kataplexy. The most, therefore, that 

 can be said for this hypothesis is, that possibly in its 

 first initiation the instinct may have been assisted by the 

 occurrence of kataplexy. 



The time during which the kataplectic stupor lasts 

 varies in different species of animals, and also in differ- 

 ent individuals of the same species. The maximum 

 duration observed in the case of rabbits was twelve 

 minutes; but fowls and guinea-pigs continue stupefied 

 for a somewhat longer time. By watching carefully for 

 the first indications of recovery, and by preventing the 

 voluntary movements in which these indications consist, 

 animals may be kept in a state of kataplexy for an inde- 

 finite time. Warm-blooded animals do not suffer from 

 such prolonged experiments ; but the latter are fatal to 

 frogs. In mammals the most characteristic features of 

 the kataplectic state, besides that of unconscious stupor, 

 are violent tremblings of the extremities, blinking of the 

 eyes, movements of the jaw and pupils, irregularity of 

 the pulse and breathing, pallor of ears in rabbits, occur- 

 rence of defaecation and micturition. On recovery the 

 abnormal state passes off suddenly, leaving the animal 

 bright and brisk as before, and thus, as in so many 

 other respects, the state of kataplexy differs from that 

 of ordinary sleep. 



One other point of interest must be noted. Preyer 

 finds that it is impossible to produce the state of kataplexy 

 in any animal that is "newly-born." In the case of 

 guinea-pigs susceptibility to be thrown into this state 

 only begins to show itself during the first week after birth, 

 and then gradually increases through two or three weeks. 

 This curious fact is explained by the hypothesis that the 

 volitional centres — or the centres which are supposed to 

 be affected by kataplexy — require some time after birth 

 to be brought into functional relation with the lower 

 centres. 



On the whole, then, it will be seen the facts relating to 

 the hypnotism of animals are much more definite than the 

 theories by which it is sought to explain them ; and 

 although we may be prepared to agree with Preyer that 

 these facts in some Avay depend on certain unusual 

 stimuli acting in some peculiar manner on some inhi- 

 bitory centre or centres, we must feel that this statement 

 of the case brings us ^only to the threshold of an 

 explanation. George J. Romanes 



HYDROGEOLOGICAL SURVEY OF ENGLAND 



"C^LOODS, or water in excess above ground, form one 

 •^ of two extreme conditions, of which the other is 

 drought, or water in defect below as well as above ground. 

 The requirements of water-supply induce the necessity for 

 storage. Out of these three simple facts arise several 

 intricate public questions. Thus it is evident that, if 

 floods are to be controlled, some one must have authority 

 over the rivers, and inasmuch as floods are intensified by 

 land drainage, that authority must extend over the whole 

 of the watershed area if it is to execute measures of a 

 sufficiently comprehensive character to be effective. As 

 works cannot be constructed without money, it must also 

 have rating powers over the whole river basin for the 

 purpose of raising the necessary funds to cover the cost 

 of such remedial works. But inasmuch as the flooded 

 lands bear a small proportion to the contributary area, 

 that is, to the rest of the watershed basin, the consequent 

 preponderance of influence and capital is largely in 

 favour of the unflooded portions. Therefore, if the case 

 of floods rested for its remedy solely upon the loss sus- 



tained by riparian owners, it is doubtful whether the 

 British public would ever be brought to see the desira- 

 bility of moving in the matter. Drought, however, is felt 

 by an increasing population, whose interest in having a 

 proper water-supply is as deep as can be desired. The 

 public looks to the engineer to provide proper storage, 

 who is thus called upon to unravel at least two of the 

 knots that surround the subject of rivers considered in 

 relation to the storage of water. The first of these is of 

 a purely physical kind, and is simply this : that whereas 

 water for the purposes of water-supply is required at 

 high levels, the pure rain which falls upon the declivities 

 of the watershed area at once proceeds to find the lowest 

 level or the deepest ruck in the valley, down which it 

 courses, along the natural main drain of the basin, and 

 below the level of all possible habitations, to the sea. 

 Therefore, before it can be used, it must be lifted out of 

 this ruck. Here steps in the second difficulty. Some 

 one has a vested right in every yard of this water, and a 

 real or supposed interest in obstructing every attempt to 

 divert any portion of it. Waterworks having rivers for 

 their sources have for these reasons proved too expen- 

 sive for scattered populations in the past. Nevertheless, 

 when fish was a necessary article of diet, the money and 

 influence were forthcoming to cause the construction of a 

 series of very noble ponds, and subsequently when the 

 manufacture of iron flourished in the south of England, 

 many more were added for the purposes of water power ; 

 while in some cases water was diverted from the main 

 channel and carried in an open conduit, as in a mill race, 

 with the same object in view. In the case of canals, 

 much of the best and purest spring water the country 

 contains has been degraded from its higher uses to the 

 purpose of a common carrier, but now that the require- 

 ments of the population have changed, and it is no longer 

 essential either for the one purpose or the other, but is 

 wanted for drinking, it should be the aim of the engineer 

 to do for water supply what has been done for water 

 power, but on a more comprehensive and extended scale, 

 viz., to keep the water as high as possible by diverting as 

 much as he can take from the upper tributaries, and 

 causing it to contour as far as possible along the ridges 

 with a view of commanding the largest extent of country 

 by gravitation, and to compensate the main channel by a 

 series of storage ponds. Numerous instances may be 

 found in the lower greensand districts in Surrey, formerly 

 a seat of the iron trade. 



As a whole, the country is more largely dependent 

 upon subterranean sources, or upon wells, for its water 

 supplies than it is upon rivers. Inasmuch as every well 

 that is sunk increases by a small amount the storage 

 capacity of the stratum, the tendency is in the direction 

 of a gradual lowering of the water-line. The resources 

 of the subterranean water systems cannot be taxed inde- 

 finitely. Under London an elliptical vortex has been 

 pumped out whose dimensions below sea-level are twenty 

 miles long, eight miles across, and 130 feet deep, the 

 total amount of depression at the apex being about 150 

 feet. Yet we have very recent instances of destructive 

 local floods in the Metropolitan area immediately above 

 this great centre of exhaustion. These two considera- 

 tions point to the multiplication of wells, coupled with a 

 proper system of replenishment from flood waters, as a 

 means of utilising these natural reservoirs. The restora- 

 tion of the original levels under London would restore to 

 upwards of one hundred square miles of country their lost 

 property as Artesian areas of overflow, the value of which 

 is such as to confer upon the surface its full value as 

 building land. 



Thus, as storage above ground is expensive, and gene- 

 rally in supposed conflict with the interests of rivers, few 

 of the numerous natural sites for reservoirs in England 

 have been utilised, except in some places in the southern 

 counties, where they were dammed up for fish ponds and 



