Sept. 15, 1882 



• KNOWLEDGE ♦ 



265 



intrref to tDc Cliitor. 



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** In knowledge, that man on 



than fiiitT of opinion," — Faraday. 



" Showme a man who makes no mistakes, and I will show von a man who has 

 done nothing." — Liebig. 



TO MR. PKOCTOR. 



[352] — Paradoxers can become indiEmaiit when contradictecl, as 

 you know, having, like myself, received some epistles from that 

 " polite letter-writer," John Hampden. What, then, mnst be the 

 state of mind of a paradoxer when his chiefest, his dearest, his 

 pettedest, his fundamental paradox is attributed to another ? You 

 have done me this wrong, and, therefore, when next we meet, &c. 



In your " paradox comer," page 250, you place Dr. Siemens on 

 my rightful pedestal. The "ingenious paradox " of supposing — aye, 

 of even assuming — that interplanetary space is occupied by water 

 is mine, and mine only. Grove and others have fiUed it with 

 oxygen and nitrogen, Sterry and Hunt with carbonic acid; but 

 " water, water everywhere " is my paradox, argued and stated as 

 the fundamental basis of my essay on " The Fuel of the Sun," 

 printed in 1S69, and published 1870. 



Hitherto none of the orthodox have attempted to refute this 

 paradox by a discussion of the arguments upon which it is based. 

 Until they do so, I shall not argne seriously with them, but merely 

 refer to Chapter III. of the above, and quote the following from " A 

 Simple Treatise on Heat," written ten years later: — 



" The water of our ocean being equally capable of evaporation 

 into the dense air immediately above it, or the lighter air above the 

 clouds, or all the boundless space stretching between the orbs of 

 heaven, be that space a vacuum or a plenum, must thus evaporate, 

 or have evaporated, into all the interstellar space until that space be 

 saturated according to its temperature, and such space must have 

 s^me temperature, seeing that it receives all the radiations of all the 

 countless suns. Therefore, the fact that our ocean is not dried up 

 indicates the existence of ' water, water everywhere,' filling all the 

 interstellar and interplanetary space of the universe, and having 

 its density proportionate to its temperature" (i.e., the temperature 

 of space). 



The above passage is corollary to any exposition of the general 

 elementary facts of aqueous evaporation, more especially of the 

 law that water is evaporated into the space surrounding it and 

 saturates that space, be it vacuous or filled with much or little of air 

 or other gases ; or, " in other words, that the limit of evaporation of 

 liquid water into surrounding space is simply a function of tempe- 

 rature, and not of the previous contents of that space." 



I have heard of people who aflRrm that space has no temperature, 

 and at the same time that our sun, and all the other suns of the 

 universe, are dying out or cooh'ng down. These orthodoxers then 

 take another breath, and assert that heat is force, or a mode of 

 motion, and that force and motion aro indestructible. Then 

 another breath, and further assort that lieat is transmitted by the 

 oscillations, gyrations, collisions, Ac, of material particles ; then 

 another, and that there are no material particles between the sun 

 and the earth. 



As I refer to orthodoxers, and not to paradrxers, I mnst wjite 

 courteously, otherwise I should say that they do this all in one 

 breath. \V. M.trrtEU Williams. 



[Is it paradoxical to suggest that there may be aqueous vapour 

 in interplanetary space ? A very clever correspondent of the 

 Enylifh Mechanic in former times — I forget how far back — Mr. K. 

 L. Garbett, used to maintain that some comets are aggregations of 

 the water of space — I think he even adopted Whiston's notion, that 



the Biblical flood was brought about by a big water comet. That, 

 of course, was paradoxical. But the idea of aqueous vapour in 

 space is reasonable enough. Paradox comes in when we try to 

 get terrestial hailstorms out of it. — Ed.] 



ARTIFICIAL STONE. 



[553] — The utilisation of refnsc opens up a largo field for 

 scientific investigation. Much has already been done, thousands 

 of pounds have been saved annually, many manufacturers have 

 arisen, and consequently work has been found for thousands of 

 people, solely on accotmt of discoveries made in this department of 

 research. 



A good example of making waste matter into a marketable 

 product is afforded by the manufacture of artificial stone. 



This stone can be used for a great variety of purposes, chief 

 among them being for paving, edging for paths and gardens, 

 but chiefly for building. It is easily worked, and can be 

 made into any design, and at a short distance it cannot be dis- 

 tinguished from real stone. It has many advantages over real stone. 

 It is much cheaper ; it gets harder and harder for at least seven 

 years ; it does not break up in frosty weather ; and lastly, it does 

 not discolour when exposed to the atmosphere. 



The larger kinds of stone-work are made in wooden moulds. A 

 layer of plaster two inches thick, generally composed of one part of 

 Portland cement and two parts of stone dust, is spread evenly over 

 the bottom and sides of the mould ; a mixture of brick rubble, broken 

 up small, and coke breeze, both of which have been previously well 

 washed, are worked up with Portland cement, and then put into the 

 mould and rammed well in. Another layer of plaster is then pnt 

 over this, and the whole left to dry fcr a week. The moulds and 

 their contents must be kept under cover. This is specially needful 

 in frosty weather, as if they are left out when freshly made for a 

 single night the stones break all to pieces. But when once they 

 are properly drj', they will stand any amount of cold. 



The facing for paving stones, as they have to stand a good deal 

 more wear, is made of a mixture of sand and Portland cement in 

 equal proportions. Ee.ve.st L. R. 



HIGHLAND CELTS. 



[554] — In reply to A. H. : — (1.) Any person who reads and 

 speaks Gaelic, or has adictionary, knows that "donn" and "dubh" 

 are in Gaelic as distinct as brown and black in English. 



(2.) Tacitus, he says, uses a word meaning " unmitigated 

 carrots." This word, however, also means golden and bright 

 yellow, colours frequent amongst us Caledonians, but invariably 

 tinged with brown. Tacitus himself shows that he means the 

 latter, as he says it points to a German derivation of our race. 

 That the Germans are a fair and not a red-haired race we all know, 

 and A. H., not to go further, says so in his letter. 



(3.) We have the astounding statement that Breadalbane lies 

 south of the Grampians. I live in the centre of Breadalbane, with 

 a range of the Grampians to the south. The battle of the Grampians 

 was fought still further south. 



(4.) A. H. says that but little Gaelic is spoken in our conntiy 

 parishes. To one living, as I do, near Killin, to put it mildly, this is 

 nonsensical. 



(5.) He says the Caledonians are described as a mixed race. I 

 ask where ? Certainly not in the ancient chronicles and ancient 

 Gaelic poetry. Xor yet can it be found in unwritten tradition, 

 usages, names of places and sculpture. In point of fact, Breadalbane 

 (especially western) is the very acme of unmixed Caledonianism. 

 All modern authorities I positively refuse to accept, as the bulk of 

 them have no real knowledge of ns, our language, poetry, usages, 

 i-c, and betray their ignorance at every turn, as " .\. H." does. 



Xow for facts. On 27th instant there were present at Killin 

 Public School 63 scholars, and of these 51 had brown hair and blue 

 eyes; 11 brown hair and brown eyes; 1 red hair; and with black 

 hair and black eyes, none. At Kenmoro (eastern Breadalbane) 

 Public School there are at present 100 scholars. Of these, 48 have 

 brown hair and blue eyes ; 43 bro^»n hair and brown eyes ; 6 red 

 hair and blue eyes ; 2 black hair and dark brown eyes ; and one, a, 

 stranger, from London, black hair and black eyes. These are 

 certified in writing by the respective teachers. 



Charles Stkwart. 



BR.UX WAVES AXD MEMORY. 



[555]— May I compare or connect Dr. Muirhead's theory [Mr. 

 Knowles's] given in Knowlepce. Aug. 4, with a theory as to memory ? 



1. Physical memory— i.'., the memory by which bodily move- 

 ments are performed. Here, the frequent renewal of the same 

 impression on the nerve cells by efferent impulses, and connected 



