Darwin the Geologist

Anthony Smith graduated from Christ’s College Cambridge in 2005 with a degree in Natural Sciences. He went on to become the sculptor of the Sedgwick Museum’s bust of Charles Darwin. In this article he explains some of the steps that went into creating a bronze likeness of the man who inspired his university studies:

The design – The bust is twice-life-sized, and is based upon the young Darwin statue that I created for Christ’s College.

Constructing the armature – an armature was constructed using wood, wire and polystyrene, to support a surface of clay.

Sculpting – the sculpting was done using clay, with the portrait based on the work which I had done for the young Darwin statue (which involved researching all the available images of Darwin, written descriptions, and very helpful feedback from some of Darwin’s direct descendants).

Moulding – once the clay sculpture is completed a mould is made. First the clay is coated with about half an inch of silicone rubber. Next a multi-piece fibre-glass casing is made over the rubber. The rubber and fibre-glass is then peeled off the clay leaving a perfect impression of the clay’s surface.

The wax – the rubber is then used to make a hollow wax replica of the sculpture, with rods of  wax to help the the molten bronze flow, and the gases escape during the casting. This, and the next steps, were done at the Morris Singer Art Foundry.

The investment – the wax replica is then coated inside and out with fire-proof ceramic, these start off as fine powder, to capture the detail of the wax surface, and successive layers get thicker and thicker.

The casting – Next the wax is melted out of the ceramic to leave a hollow shell. The ceramic is supported in sand and molten bronze is poured into the gap. Once this has cooled the ceramic is broken off to reveal the bronze.

The chasing – the ceramic is then cleaned off and the bronze ’sprues’ removed.

The patination – This is one of the most exciting parts of the process of creating a bronze – the point at which it changes from being a shiny piece of metal into a sculpture. The bronze is heated up with a blow-torch and various chemicals are added which will react with the surface of the heated bronze and permanently stain it, giving it its unique ‘patina’.

Installation and unveiling – Special steel fixings were made in order to mount the bronze on the wall of the Museum. The bust was unveiled by renowned historian Janet Browne on the 6th of July, 2009.

It gave me great pleasure to sculpt this bust of the young Darwin for the Sedgwick Museum, and I hope that it will be seen as a fitting tribute to a remarkable young Geologist, who went on to challenge our understanding of the world.