digraph Weight {
bgcolor="transparent";
node [shape="rectangle", style="filled", fillcolor="white", color="black"];
edge [color="#555555"];
# add colors, distinction for records!

dram  [shape="record" label="<apt> Apothecary | <adp> Avoirdupois | dra(ch)m"];
ounce [shape="record" label="<troy> Troy | <tower> Tower | <adp> Avoirdupois | ounce"];
pound [shape="record" label="<troy> Troy | <ldn> London | <merc> Merchant | <tower> Tower | <adp> Avoirdupois | pound"];
stone [shape="record" label="<ldn> London | <merc> Merchant | <butch> Butcher | <adp> Avoirdupois | stone"];

quarter [shape="record" label="<all> quarter, tod | <long> long | <short> short"];# 1/4 hundredweight
#quintal [shape="record" label="long | short | <all> hundredweight,\n quintal, centner"];
quintal [label="hundredweight,\n quintal, centner"];# 100 pound
#ton     [shape="record" label="long | short | <all> ton"];
ton     [label="ton"];

grain;
penny [label="pennyweight"];
clove [label="clove, nail"];# nail: 1/16 hundredweight

# ounce  pound  stone   (gr)
# 450    5400           Tower
# 480    5760           Troy
#        6750   81000   Merchant
# 437.5  7000   98000   Avoirdupois
#        7200   90000   London

# ounce -> pound
	ounce:adp   -> pound:adp  [label="16"];
	ounce:troy  -> pound:troy [label="12"];
	ounce:troy  -> pound:ldn  [label="15"];
	ounce:tower -> pound:tower[label="12"];
	ounce:tower -> pound:merc [label="15"];
	ounce:tower -> pound:ldn  [label="16"];
	
# Avoirdupois
	grain -> pound:adp [label="7000"];
	dram:adp -> ounce:adp [label="16"];
	pound:adp -> clove [label="7"];// 49000 gr
	clove -> stone:adp [label="2"];// 98000 gr
	pound:adp -> quarter:short [label="25"];// 175000 gr
	stone:adp -> quarter:long [label="2"];// 196000 gr
	quarter:all -> quintal:all [label="4"];// 700000 gr
	quintal:all -> ton:all [label="20"];// 14000000 gr

# Troy, Monetary
	grain -> penny [label="24"];// 24 gr, headlabel="Troy"
	penny -> ounce:troy [label="20"];// 480 gr
	grain -> ounce:tower [label="450"];// 450 gr
	ounce:troy -> mark [label="8"];// 3840 gr
	penny -> shilling [label="12"];// 
	shilling -> ounce:troy [style="invis"]; // invisible
//	mark -> pound:troy [label="1½", style="invis"];// invisible
	shilling -> pound:troy [label="20"];

# Apothecary
	grain -> scruple [label="20"];// 20 gr
	scruple -> dram:apt [label="3"];// 60 gr
	dram:apt -> ounce:troy [label="8"];// 480 gr

# Mercantile
	pound:merc -> stone:merc [label="12"];
	pound:adp -> stone:butch [label="8"];
	pound:ldn -> stone:ldn [label="12½"];
//	stone:adp -> sack [label="26"];
	quarter:long -> sack [label="13"];
}