130 Intelligence and Miscellaneous Articles. 



deep thinking" he makes with his pen the erasures and interlinea- 

 tions which we have exhibited above. 



The first 120 pages being made up in this way, whence the other 

 portion of the book is derived we have not taken the trouble to ascer- 

 tain. Before we turn to the second part, we will just quote a passage 

 from the Preface : " That it has no pretensions to the title of a scien- 

 tific treatiseis self-evident — (who will doubt this ?) — the author's ob- 

 ject in the first part of the work, being simply so to explain the se- 

 veral varieties of electrical action as to enable the non-scientific 

 reader to understand the modus operandi (!) of the electric fluid in 

 producing the different phsenomena which are treated of in the se- 

 cond part." Some may be rather curious to know now of what the 

 second part is made up, after the statement of " one so humble in the 

 ranks of science" ; and they will no doubt be astonished to learn that 

 it treats of nothing less than cholera morbus, phsenomenaof disease, 

 inflammation, fever ; the modus operandi of the electric fluid in im- 

 parting their forms to vegetables and animals ! and that it is neither 

 more nor less than an electrical dream of Mr. Leithead's fancy. And 

 all this for non-scientific readers, in a treatise on electricity. The 

 cholera morbus is made to depend on aurora borealis, shooting stars, 

 &c, ; and the vital principle to be probably identical with the elec- 

 tric fluid. Mr. Leithead, moreover, sees " no reason why water 

 should not be composed of hydrogen and oxygen in the planet 

 Mercury, as is the case on our earth," for he conceives " that the 

 degree of force with which an atom retains its electro-polarity on 

 any of the heavenly bodies, will bear some exact ratio to their 

 distance from the sun." — p. 397. 



We have nothing further to say of this notable production ex- 

 cepting that its price is eight shillings, whilst the two numbers of 

 the Library of Useful Knowledge are sold for sixpence each. 



XXI. Intelligence and Miscellaneous Articles, 



ABSORPTION OF WATER BY EFFLORESCENT SALTS. 



MR. HUGH WATSON in a paper read before the Philosophical 

 Society of Manchester, observes, " Hitherto I have considered 

 those salts which are usually described as efflorescent salts, to be such 

 as would effloresce whenever they were left exposed to an atmosphere 

 not saturated with vapour, but capable of evaporating water ; and 

 I believe that the same idea is generally entertained on the subject. 

 Now the result of my investigation furnishes the proof that such an 

 idea is not a correct one ; it shows that the crystallized sulphate 

 and carbonate of soda, which are generally considered as very efflo- 

 rescent salts, may be left exposed to the atmosphere for any length 

 of time without efflorescing in the least, or losing a single particle of 

 water of crystallization, though that atmosphere be dry and capable 

 of evaporating water, so long as its evaporating poxuer isjiot allowed 

 to extend beyond a certain point ; this point differs for each salt. 



In order to find how much water pure anhydrous carbonate of soda 

 is capable of absorbing, 1, on the 20th October, 1835, put 474< 

 grains = 1 atom (supposing the atom of soda to be 28, and that of 



