But if the Romans were not great navigators nor even a race of seamen, at any rate they were very fine shipwrights. Expert opinion of to-day, arguing from the evidence of the only Roman craft which are still in existence, gives the highest praise to the art of the Roman shipbuilder. The relics of the craft found in Lake Nemi were discussed by me in another volume,[16] and need be referred to now only slightly. But the other craft which was recently unearthed whilst excavations were being made in 1910 at Westminster, on the site for the new London County Council Hall, is far more instructive, because being above ground it is get-at-able and capable of intimate study. It now lies among the collection of the London Museum in Kensington Gardens. This craft was probably one of the fleet of Carausius, who for a time was admiral under Maximilian and Diocletian, but subsequently rebelled against the Imperial authority and proclaimed himself emperor of Britain in A.D. 287. [Illustration: Ship of the Roman Period discovered at Westminster. SKETCH SHOWING THE INTERIOR OF HULL.] This boat was found lying on a shell sand which indicated the original bed of the Thames. The date is approximately fixed by the three coins which were found with the boat: one of Tetricus the Elder in Gaul (A.D. 268–273), the second of Carausius in Britain (A.D. 286–293), and the third of Alectus in Britain (A.D. 293–296). It is possible that there was some ceremony in placing coins in a Roman boat, just as to-day coin of the realm is placed at the laying of a foundation-stone. She was probably a single-decked war-galley, built in Gaul, but had been dismantled before being abandoned to sink in the waters of the Thames. One expert naval architect, who made a careful inspection of this relic when first discovered, has gone so far as to state that not only is the craftsmanship excellent, that probably nothing built in our own time would look so well after seventeen hundred years’ immersion, but that finer fitting could not be expected to-day. It shows, further, not merely good workmanship, but good design. It is more than likely that this ship was built at Boulogne on one of the Roman shipyards there, and formed originally a unit in the Classis Britannica. There is a votive tablet preserved in the Boulogne Museum, and found in that neighbourhood, depicting two triremes with the stern steering oar, the beak at the bows, and the banks of oars, which shows how similar these Romano-British ships were to the Mediterranean model. The votive offering in question had been made by the crew of a trireme named the _Radians_. Possibly the Westminster ship was the flagship of Carausius.