534 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



they deem accordant with reason, that in the end it will appear that nature 

 has not made the safety of life and the profit of carriers absolutely incom- 

 patible. 



The committee have deemed it proper to make this report, not as a com- 

 plete fulfillment of the duty assigned to them, but rather as a means of 

 attracting the attention of those who may know of other plans that merit 

 consideration, and may be inclined to promote the general object of this 

 inquiry, which is not the advantage of particular individuals or trades, but 

 the proof of whatever merit there may be in the boilers, whose peculiar 

 characteristic is that even in case of rupture they have not power to 

 destroy a vessel or otherwise endanger life. The committee are convinced 

 that there are some such boilers, and that it is the duty of liberal friends 

 of science to aid in giving them a public trial. There may be others of 

 which they are ignorant, if so, they wish to be informed of them, and take 

 this occasion to ask for information. 



T. K. FISHER, 

 B GARVEY, 

 >y. ROWELL, 



Committee. 



Mr. Fisher spoke at great length upon the subject, and thought that we 

 had had a sufficient number of accidents to life and property, resulting 

 solely by the use of unsafe boilers, and it was time that the general public 

 insisted upon a better class of boilers being used, and that those acting in 

 the capacity of common carriers should protect the lives of those they 

 carry, and if a proper boiler was more expensive in making steam, then the 

 remuneration should be in accordance. 



Mr. T. Godwin presented specimens of pure tin pipe, which he desired to 

 have referred to a committee. On motion of Mr. Stetson, the matter was 

 referred to Messrs. Stetson, Garvey and Dawson, to report upon. 



The subject for the evening was here taken up. 



Bursting of Guns. 



Mr. T. D. Stetson. — If we take a sheet of glass and fire a pistol or mus- 

 ket ball through it, we punch a hole of about the size of the ball; but if 

 we fire very slow by using a small charge of powder, we break the glass 

 to pieces; in each case we have a different effect produced, and also a dif- 

 ferent measure of force. Mr. Norman Wiard, of this city, who has had 

 large experience and great practical knowledge on the subject of guns and 

 the force of gunpowder, has arrived at an original way of testing the force of 

 gunpowder, which will materially alter the calculations of others who have so 

 far experimented on the subject, and from which Mr. Wiard concludes that 

 force of gunpowder in a cannon is from 10,000 to 12,000 pounds on the 

 square inch, and this he considers is the maximum pressure. 



To test this, take an 11-inch gun and load it with thirty pounds of pow- 

 der and solid shot — bring the muzzle close to the target where the velocity 

 is greatest, and then fire it against a plate of iron four and a half inches 

 thick, which is the orthodox thickness for target practice, and we will find 

 that the ball will break through this four and a half inches of iron; and 

 this is about the measure of what an 11-inch gun will do. Now if we mea- 



