THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

The Hartford Steam Boiler Inspection and Insurance Company makes the

following report of its inspections in January, 1871:

During the month, there were 522 visits of inspection made, and 1,030

boilers examined--853 externally and 363 internally, while 106

have been tested by hydraulic pressure. Number of defects in all

discovered, 431, of which 163 were regarded as dangerous. These

defects were as follows: Furnaces out of shape, 24--3 dangerous;

fractures, 47--25 dangerous; burned plates, 29--14 dangerous;

blistered plates, 54--10 dangerous; cases of sediment and deposit,

97--18 dangerous; cases of incrustation and scale, 70--24 dangerous.

To show how little attention is paid to the internal condition of

boilers by incompetent engineers, we copy the following from a letter

of one of our inspectors:

"In one tubular boiler I found sediment in the back end, eight inches

deep, and extending forward more than four feet. It seemed to be an

accumulation of fine scale cemented together, so that it was necessary

to break it up with a hammer and chisel before it could be removed.

The engineer said _he had cleaned the boilers only three days before_,

and objected to my making another examination. This is one of the

many cases we find, where the proprietor trusts everything about his

boilers to his engineer, supposing him to be reliable."

With such accumulation of sediment and deposit, is it any wonder that

sheets are burned? A careful engineer will understand, if the feed

water be impure, that he must blow down two or three inches every day,

or oftener, that the sediment may be removed as it accumulates, and

then an internal examination once in two weeks, or once a month, will

insure a clean boiler.

Cases of external corrosion, 26--10 dangerous; cases of internal

corrosion, 17--5 dangerous; cases of internal grooving, 28--11

dangerous; water gages out of order, 50; blow-out apparatus out of

order, 15--7 dangerous; safety valves overloaded, 40--12 dangerous;

pressure gages out of order, 54--6 dangerous, varying from -15 to

+8 pounds. (We have found several gages entirely ruined from being

frozen). Boilers without gages, 4; cases of deficiency of water,

5--1 dangerous; broken braces and stays, 31--7 dangerous; boilers

condemned, 2--both dangerous.

Two engineers were found drunk on duty, and promptly discharged. There

were 9 serious explosions during the month, by which 99 persons were

killed, and 6 wounded. Eighty-seven of the killed were passengers on

the ill-fated steamer _H.R. Arthur_, on the Mississippi River. Many

were drowned, and some burned, but the origin of the calamity was the

bad quality of the boilers, which a careless management was unable

to detect. The upper and fore part of the boat was blown away by the

exploded boilers, and, to add to the horror, what remained took fire.

None of these exploded boilers were under the care of this company.

* * * * *

Five ore-roasting furnaces are in full blast in Nevada.

* * * * *

Scientific American, Volume XXIV., No. 12, March 18, 1871 A Weekly Journal of Practical Information, Art, Science, Mechanics, Chemistry, and Manufactures. · 第 56 / 194 题