6t4 TRAXSACTIONS OF THE AMERICAN IXSTITUTE. 



Mr. Butler conceived, in that case, that it Avould cause no 

 material deviation of the shot. 



The President remarked in relation to packing, that, on the 

 New York Central Railroad, some of the boxes on which the 

 wheels had been constructed, and used for the last eight months, 

 of rings of metal filled in with a substance like papier mache. 

 The result was that there was a saving in the wear of from six to 

 seven-eights over the solid metal boxes. That might be sugges- 

 ted of the saving of the wear of the cannon by a soft packing. 



HEATING BUILDINGS BY STEAM. 



Mr. Dibben remarked that insurance companies had expressed 

 considerable anxiety of late in reference to the comparative safety 

 of different modes of heating, and they have an impression that 

 there is danger from accidental if not spontaneous combustion in 

 buildings heated by steam pipes in contact with wood. Mr. D. 

 expressed the opinion that, in consequence of a partial decompo- 

 sition of the wood near steam pipes, spontaneous combustion 

 might be possible — as, for instance, in the pine knots — the heat 

 from the steam pipe falling short of the degrees of ignition. 



Mr. Baker stated that he had been engaged for six years past 

 in putting in steam pipes, and he ran them through woodwork 

 and among shavings without any fear of combustion. He had 

 never yet known a case even of charring. It would require a 

 pressure of from 70 lbs. to 100 lbs. to produce combustion. Six 

 years ago he called the attention of insurance companies to his 

 mode of using steam without pressure, and they were so well con- 

 vinced of its safety that they made a reduction of 10 per cent, in 

 the rate of insurance. 



Mr. Fisher had seen a few cases of charring and turning to 

 ashes from steam, but it was probably caused by superheated 

 steam. Low pressure, with superheated steam, he considered as 

 liable to set fire as high pressure. He had heard of buildings 

 being set on fire by Perkins' hot water apparatus. He consid- 

 ered it desirable that the pipes should always pass through some- 

 thing that could not be set on fire, or there was danger from 

 superheated steam. 



Mr. Baker said that it had been stated in the Scientific Ameri- 

 can that steam pipes were dangerous, and an open fire was the 

 safest. In the year 1858 or 1859 there were about 200 deaths 

 in the city of New York by setting fire to clothes. 



