CRITTCAL NOTICES OP NEW PUBLI€ATIONS. 163 



quently a small taper, previously lighted, is immediately extinguished' in the 

 space intei'vening between the central wick flame and the cage. It must be 

 obvious that the enclosure, on these principles, can never be filled with 

 flame, and the gauze cannot be made red hot. 



** That Messrs. U. and Il.'s Safety Lamp must eventually supplant 

 Davy's imperfect one, is suflicientiy obvious, though I still think the compa- 

 rative safety of ' The Davy Lamp' may be considerably enhanced and im- 

 proved by the means I have already suggested ; freely admitting, at the 

 same lime, that I cannot conceive it possible, by any improvement whatever, 

 to enable it to encounter the supposeable contingencies of the mine, to the 

 full amount of that of Messrs. Upton and Roberts. » « * Whether le- 

 gal enactment will banish the Dav}' Lamp altogether from mines, and sub- 

 stitute exclusively the Safety Lamp of U. and R., I cannot pretend to di- 

 vine ; but this I know, that the coal proprietor will be as deficient in huma- 

 nity as he is wanting to his own interests, if he hesitates to substitute the 

 latter for the equicocal safety promised by the ' Davy :' while he halts be- 

 tween two opinions, the work of destruction may occur.** 



The postscript to this pamphlet, which is deserving the especial 

 attention of the philanthropist and the man of science, contains 

 some valuable hints for preventing the bursting of steam boilers — 

 on the phenomena of decay in timber, called the dry rot — and on 

 the application of paragreles to hop grounds, as a preservative from 

 blight and aphides. 



As the application of steam is so extensively employed for manu- 

 facturing purposes in this district, we are induced to allude to 

 that subject. Mr. Murray ascribes the explosion of steam boilers 

 to sudden extrication of steam from limited portions or local patches 

 at the bottom of the boiler, arising from the unequal dhtribution 

 of the heat below, conjoined with the imperfect ci>nductibility of the 

 water ; in which case the so called ' safety valve* is of no use We 

 must refer our readers, for the present, to the work itself for the 

 means pointed out by Mr. Murray for security against accidents of 

 this nature ; but we shall probably revert to the subject more at 

 length in our next publication. 



The pamphlet is printed on the first paper ever manufactured 

 from Phormimn tenax, or New Zealand flax (unbleached J. This 

 paper possesses a smooth surface, with a remarkably firm texture ; 

 and if the raw material had undergone the process of bleaching, it 

 would have been fully equal in quality to the best paper manufac- 

 tured from linen rags. Mr. Murray states that this plant, hitherto 

 an inmate of the green-house, might be successfully cultivated in 

 the climate of Scotland, where he has specimens growing on a poor, 

 light soil, seven feet high, which have withstood, without the 

 slightest protection, the severity of seven Scottish winters. We 

 hope the government will, at no very distant period, turn their at- 

 tention to this subject, and weigh the advantages of occupying the 

 unemployed agricultural labourers in the cultivation of the Phor. 

 mium tenax on the waste lands belonging to the crown, in lieu of 

 promoting emigration to distant colonies. 



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