Tratis. N. Y. Ac. Sci. 78 A^''- 29,- 



were discussed : coal-tar : paint, which has been used in New York 

 for many res'dences, as in Washington for the Capitol and in London 

 for Buckingham Palace, etc., but lasts only a few years and often even 

 permits the disintegration to progress beneath it : oil, often used in New 

 York, but as objectionable as paint : soap and alum-solution : and 

 paraffine, beeswax, rosin, t?l!ow, etc., dissolved in naphtha, turpentine, 

 camphine, oil, etc. 



The preparations of an inorganic nature, which have been proposed 

 and used abroad, have in some cases met with succf ss ; but the exact na- 

 ture of their f.ction, and the conditions to which they are each suited, are 

 yet to be investigated, especially with reference to ihe entirely different 

 climate by which the stone in our city is being tried. The processes 

 which have been proposed, and in some cases practically used, involve 

 the application of the following substances : waterglass, in connection 

 with salts of calcium or barium, or bitumen : oxalate of alumiinum : 

 barium solution, in connection with calcium superphosphate or ferro- 

 silicic acid ; copper salts, used by Dr. Robert in Paris to stop the growth 

 of vegetation en stone, etc. . There is certainly a call for processes by 

 which, at least, those stones which are used in isolated, exposed, and 

 unnatural positions, may receive artificial protection, such as the stone- 

 sills and lintels of windows, stone balusters, projecting cornices, and 

 ashlar-stone set up on edge. It will doubtless be found that only those 

 stones, which possess a coirse porous texture and strong absorptive 

 power for liquids, will be found particularly available for protection by 

 artificial preservatives, and that such stones should indeed never be 

 used in construction in a raw or crude state. In the spongy brown 

 and light olive free-stones, a marble full of minute crevices, and a cellu- 

 lar fossiliferoDS limestone, a pe'rifying liquid may permeate to some 

 depth, close up the pores by its deposits, and encase the stone in solid 

 armor; while, upon a more compact rock, such as a graryte or solid 

 limestone, it can only deposit a shelly crust or enamel, which time may 

 soon peel off. The carelessness with which stone is selected and used, 

 and the ignorance m regard to i's proper preservation, when the decay 

 of a poor stone becomes apparent, have led to ap increased use of 

 brick and terra cotta, much to be deplored ; durable stones are to 

 be obtained in great variety, methods for the preservation of the porous 

 stones can easily be devised, and stones of afire-proof character do exist 

 in this country in abundance. 



In conclusion, three suggestions were offered: ist, that householders 

 invoke the magic use of the broom on the fronts of their residences as 

 carefully as upon the sidewalks : 2d, that house builders insist upon the 

 undercutting of all projections, and the exclusion of brackets or other 



