TESTIMONIALS.

137

“ LiDcoln’s.Inn, Jan. 10, 1849.

“ Sir,—I beg to inform you,that the Patent Fire-proofChest, which I purchased fromyou about eighteen months ago,was exposed to the fire whichdestroyed No. 2, New Square,on Sunday last. The safe wasfull of deeds and papers. Afew of the deeds which were inimmediate contact with the topof the chest, and which appearsto have been exposed to thefiercest heat, are in some degreeinjured, being shrivelled in parts;but, I believe, will not prove tobe illegible. All the rest ofthe documents, being more thannine-tenths of the whole, arequite safe and uninjured,

“ I am, sir,

“ Yours faithfully,(Signed) “JOHN MARTIN.”

“P.S. — The safe was ex-posed to the fire for a period ofthirty-four hours.”

“ To Mr. Harr, 52, Cheapside.

This Testimonial,which is doubtless so farcorrect, as to confirmwhat I have before statedas to the impossibility ofpreserving parchment inan iron safe, whethermade fire-proof, as thiswas, on the principle ofnon-conduction only, (seeMarr’s specification, page11 ,) or that of evapora-tion. The injury to “afew of the deeds” (parch-ment) is not attributedto the natural conse-quences of intense heatacting on such a sub-

stance, “ for a period ofthirty-four hours,” but tothe accident of thesedeeds being “in imme-diate contact with thetop of the chest.” Asiron is one of the best conductors of heat, it issimply impossible to make a safe so hot that itshall injure deeds at the top, without in the samedegree injuring those situated in other parts.It implies that the top plate of the chest was hot,while the others w'ere cool. From some of the