Useful information (for me)

I have not read March's classic work, British Destroyers, cover-to-cover. I was reading the section about the V-class from WWI, and saw that he listed some useful weights. For example, the H-type mine with Mk.VIII sinkers weighed 1,840 lbs. With the smaller 21in torpedoes previously in use, the two triple tube mounts in the W-class were 20-1/2 tons. With the new, larger 21in torpedoes, the weight jumped to 32-1/2 tons. This is from pp.206 and 207. This is probably only of interest to those who want to design their own destroyers and minelayers: people like me.