Proceedhiffs of the Society; of Arts. 401 



subject of Life Assurance before the Society, and in particular for his ex- 

 position of the errors of the honus sj'stem. It was understood that papers 

 taking, in some respects, an opposite view of this intricate subject are to 

 be given in and read before the Society. 



2. On a new Scale for the Thermometer. By James Hunter, Esq. of 

 Thurston, M.S. A. Thanks voted, and referred to a Committee. (G88.) 



3. On a new kind of Ink, obliterated with great difficulty. By Andrew 

 Fyfe, M.D., F.R.S.E., M.S.A. Thanks voted, and referred to a Commit- 

 tee. (691.) 



4. Donation — An Account of a Series of Experiments made with a 

 large Magneto-Electrical Machine. By Mr E. M. Clarke, philosophical 

 instrument-maker. Strand, London. Presented by the Author. Thanks 

 voted. (686.) 



The following Candidates were admitted as Ordinary Mem- 

 bers, viz. : — 



John Cockburn, Esq. 6 Douno Terrace ; John Fraser jun. Esq. (of 

 Standard Life Assurance Office), 23 Sciennes Street ; Thomas Scott, Esq. 

 accountant, 19 St Andrew Square; Hugh S. James, Esq. Edinburgh. 



26M February, 1840. — Sir John Graham Dalyell, President, 

 in the chair. The following communications were made : — 



1. Notice on the use of Brass or Copper Plates, having their surfaces 

 Silvered, for producing Pictures by the process of Daguerreotype. By Mr 

 John Adie, optician, 58 Prince's Street, M.S.A. A specimen was exhibited. 

 (692.) Referred to a Committee, and to be printed. 



2. Model and Description of an Improved Railway Crossing. By Mr 

 John Meiklejon, engineer, 39 Home Street, Edinburgh. (689.) Re- 

 mitted to Messrs Grainger and Miller to try practically. 



3. Verbal Notice of Sir W. Burnet's Process for the prevention of Dry 

 Rot ; with illustrative specimens. By Dr D. B. Rcid, F.R.S.E., M.S.A. 

 (695.) This process consists in applying a solution of Muriate of Zinc 

 to the cloth or other substance to be preserved. It is very much cheaper 

 than where preparations of Mercury are used ; and to shew how well it 

 acted, Dr Reid exhibited two sets of specimens, in every respect alike, of 

 soldiers' cloth, sail cloth, ropes, &c., which were placed and kept for u 

 year in one of the dampest cellars in Somerset House, the one set being 

 in their natural state, and the other impregnated with the Muriate of 

 Zinc ; and while the former were quite rotten, had lost their colour, and 

 were easily torn to fragments, the latter were as fresh in colour, and as 

 strong in texture, as when they were put in. It is understood that a 

 patent has been taken out to secure this valuable invention. The thanks 

 of the Society were given to Dr Reid for exhibiting the specimens. 



1. The Report of the Committee on Mr Dunn's Improvement on the Re- 

 gistering Thermometer was read and approved of. Dr Fyfe, Convener. 



5. The Report of the Committee on Mr Galpin's Photographic proccii 

 was read ivnd approved of. Dr Fyfe, Convener* 



