11. =_Don’t_= let any dampness get into the boiler and pipe coverings.

12. =_Don’t_= fail to see that you have plenty of water in the boiler

in the morning.

13. =_Don’t_= fail to keep the water at the same height in the boiler

all day.

Maxims and Instructions for the Boiler Room Useful to Engineers, Firemen & Mechanics; Relating to Steam Generators, Pumps, Appliances, Steam Heating, Practical Plumbing, etc. · 第 36 / 328 题