Aug. 1, 1884.] 



♦ KNOAAALEDGE 



87 



out the dangerous ground, whilst the two last-named bodies 

 remain inert, or, at least, expend an enormous sum of 

 money per day on chloride of lime.* In the meantime Dr. 

 Koch's comma-like cholera germ awaits but an opportunity 

 for establishing itself in our midst. We cannot refrain 

 from expressing our opinion that it is "passing strange" 

 that all this misdirected expensive energy should exist, 

 when numerous well-devised, inexpensive, nay jirqfitahlc 

 methods, for counteracting all ill-effects are easily available. 

 It shall be our duty in future pages to give a detailed 

 account of some of these. 



We have already said enough about germs and their 

 agency in producing chemical poisons or ferments, and 

 upon decaying animal and vegetable structures in water to 

 seriously alarm the more apprehensive of our readers. It 

 is best, however, " to err on the side of safety," but we 

 most emphatically disagree with " W. C. B.'s" address to 

 our editorial fountain-head, which we requote here as an 

 extraordinary sanitary curio.sity : — 



" W. C. B." (lemurs to the idea that a polluted river is neces- 

 sarily unwholesome, as over and on the banks of one — " a mass of 

 festering filth, chocolate in colour, molasses in consistency, and of 

 stench simply indescribable " — many of his workpeople live, halo 

 and hearty, as did he and a large family for fifteen years. More- 

 over, twenty cows, always well and thriving;, drink this filth in 

 preference to pure spring water. 



To which our "E. F." aforesaid curtly replies : — "Just 



so; de guslihus non est dispu/andum 



which, being 



freely translated, would sound very like the olden English 

 saying, " There 's no accounting for tastes, as the old 

 woman said when she kissed her cow." 



Nevertheless, organically polluted waters, of which 

 sewage is a type, do undergo a process of natural purifi- 

 cation. The organic matter consists chiefly of azotised sub- 

 stances and hydrocarbons ; and the water, in its passage 

 along rivers or through the soil, takes up a large proportion 

 of oxygen, which in its turn reacts upon the former, con- 

 verting them into useful nitrates ; and upon the latter, 

 causing them to give forth the equally valuable carbonic 

 acid gas. But these processes are necessarily tardy, and, 

 in the majority of cases, but imperfectly carried out. The 

 water of rivers containing sewage is, moreover, not only 

 prone to be temporarily imsuitable for domestic purposes, 

 but it contains in addition chemical poisons, which result 

 from the fermentative action of putrefactive agents, which 

 no process of oxidation can ever eradicate. Whether 

 these ferments are generated in sufficient quantity to render 

 certain streams and rivers detrimental to the life of plants 

 and fish, yet remains to be investigated ; but we may safely 

 argue from premises such as the above, that a prolonged 

 discharge of sewage into rivers clearly points to a termina- 

 tion which must inevitably be disastrous to both plant and 

 animal life. 



We shall hereafter pass on to consider in detail the 

 varieties of water suitable for specific purposes, the tests 

 to be used in the determination of their respective values, 

 and the means which have been adopted by recent inventors 

 to meet all demands. 



A Simple Scxshine Eecorder. — Professor Herbert llacleod, of 

 Cooper's Hill Engineering College, has devised a simple and effective 

 sunshine recorder by merely placing a globular bottle of water (or 

 water lens) in front of the lens of a camera in such a position that 

 the focussed ray falls on a sheet of sensitised paper spread on the 

 bottom of the camera box. A curved white line or band is pro- 

 duced on the paper as the sun revolves, and when clouds cross the 

 sun the line stops. — Enijineeriiig. [I have often wondered that 

 some such simple contrivance has not been devised before. The 

 price at which so-called " sunshine-recorders " are sold is exorbitant. 

 —Ed.] 



* Cf. Daily Telegraph, July 16, ISSi. f " tJt Supra," page Gl. 



OTHER WORLDS THAN OURS. 



A WEEK'S CONVEHSATION ON THE PLURALITY OF 

 WORLDS. 



By Moks. de Fontenelle. 



with notes by richard a. peoctoe. 



{Continued from p. 70.) 



" "f TTHEN they had ranked the heavens in the manner 



W you tell me, pray what is the next question?" 

 " The next," said I, " is the disposing the several parts of 

 the universe, which the learned call making a system ; but 

 before I expound the first system, I would have you ob- 

 serve, we are all naturally like that madman at Athen.s,* 

 who fancied all the ships were his that came into the 

 Pyrwum port. Nor is our folly less extravagant ; we be- 

 lieve all things in nature designed for our use ; and do but 

 ask a philosopher, to what purpose there is that prodigious 

 company of fixed stars, when a far less number would per- 

 form the service they do us 1 he answers coldly, they were 

 made to please our sight. Upon this principle, they 

 imagined the earth rested in the centre of the universe, 

 while all the celestial bodies (which were made for it) took 

 the pains to turn round to give light to it. They placed the 

 moon above the earth. Mercury above the moon, after 

 Venus the sun. Mars, Jupiter, Saturn ; above all these they 

 set the heaven of fixed stars, the earth was just in the 

 middle of those circles which contain the planets ; and the 

 greater the circles were, they were the farther distant from 

 the earth, and by consequence the farthest planets took up 

 the most time in finishing their course, which in effect is 

 true." 



" But why," said the Marchioness, interrupting me, " do 

 you dislike this system 1 It seems to me very clear and 

 intelligible." 



" However, Madam," said I, " I will make it plainer ; 

 for should I give it you as it came from Ptolemy its author, 

 or some others who have since studied it, I should fright 

 you, I fancy, instead of diverting you. Since the motions 

 of the planets are not so regular, but that sometimes they 

 go faster, sometimes slower, sometimes are nearer the earth, 

 and sometimes farther from it ;t the antients invented I 

 know not how many orbs or circles involv'd one within 

 another, which they thought would solve all objections : 

 This confusion of circles was so great, that at that time, 

 when they knew no better, a certain King of Castile, a 

 great mathematician, but not much troubled with religion, 

 said, ' That had God consulted him when he made the 

 world, he would have told him how to have framed it 

 better.' The saying was very atheistical, and no doubt the 

 instructions he would have given the Almighty, was the 

 suppressing those circles with which he had clogg'd the 

 celestial motions, and the taking away two or three super- 

 fluous heavens which were plac'd above the fixed stars : for 

 the philosophers, to explain the motion of the celestial 

 bodies, had above the uppermost heaven (which we see) 

 found another of crystal, to influence and give motion to 

 the inferior heavens ; and where-ever they heard of another 

 motion, they presently clapp'd up a crystal heaven, which 

 cost 'em nothing." 



" But why must their heaven be of crystal," said the 

 Marchioness ; " would nothing else serve as well t " 



" No, no," replied I, " nothing so well ; for the light was 

 to come thro' them, and yet they were to be solid. Aristotle 



* The reasoning here closely resembles that which the modem 

 student of the subject has to employ. — E. P. 



t Sometimes advance and sometimes retrograde, he should have 

 added.— R. P. 



