Vikings of Bjornstad - Norse Mythology

The Vikings of Bjornstad

The Long Ships (1964)
Image source: The Long Ships (1963)
Towing the "Mother of Voices" Golden Bell: How Big Would the Barge/Raft Have to Be?
Stealing a massive golden bell named "The Mother of Voices"- and transporting it on a raft towed behind a Viking longship - are part of the fun in the 1964 movie The Long Ships. If you're like us, the questions that come to mind are driven by the substantial weight of that much gold. We wondered how much a bell that size would weigh, and how large a raft would be required to keep it above water. Below is an attenpt to come up with the answers. We made some "reasonable" assumptions, but aren't completely assured of the accuracy of the results. If you have suggestions to improve the calculations, let us know. We left the spreadsheet's spurious calculation accuracy decimal places intact for fun...

Measurement	Metric		Imperial		Notes
Size of the Mother of Voices based on the photo of man and bell
Height of a Viking man in photo	60	mm			Measured directly from video screen capture
Height of a Viking man for reference	1.8288	m	6	ft	Baseline, assumed for simplicity
Width of bell base	125	mm			Measured from video screen capture
Resulting single dimension ratio	2.083333333				Ratio of man height to bell base width
Calculated bell base diameter	3.81	m	12.5	ft	Based on man height to bell width

Bell Weight Standard - assumed bronze					(Note that Notre Dame bell thickness is about 16 cm, roughly the same as the Mother of Voices)
Notre Dame bell base diameter	2.62	m
Notre Dame bell weight	13	tons	14.33003	tons	Includes 500 kg for clapper
Notre Dame bell weight without clapper	12.5	tons	13.778875	tons	Without clapper

Calculated Mother of Voices weight, if bronze
Ratio of bases	1.454198473				Notre Dame and Mother of Voices base widths compared
Ratio of masses	3.075183622				Ratio of bases³, resulting from height, width, depth multiplication
Calculated Mother of Voices weight if bronze	38.43979528	tons	42.37257074	tons	Multiplication of Ratio of masses times Notre Dame bell weight without clapper

Standard metal weights					https://roofonline.com/weight-of-metal/
Bronze weight	8.86	g/cm³	553 lb/ft³
Gold weight	19.32	g/cm³	1,206.1 lb/ft³
Resulting metal weight ratio	2.180586907				Gold weight compared to bronze weight

Calculated Mother of Voices weight, if gold
Bronze weight * metal weight ratio	83.82131431	tons	92.39707298	tons	Not sure how a golden bell would sound, but that's not the issue here :-)

Standard Barge Capacity					Google: "barge capacity chart"
Barge deck size	634.062975	sq m	6825	sq ft
Capacity	1360.778728	tons	1500	tons

Barge requirement
Calculated barge ratio	0.061598049				Comparison between standard barge capacity and the Golden Bell weight capacity needed
Calculated deck size requirement	39.05704198	sq m	420.4066821	sq ft	Barge area needed based on Standard Barge Capacity and Calculated barge ratio
Calculated deck length & width requirement	6.25752426	m	20.50382116	ft	Linear size of barge needed (square root of deck area)