Remus Aer Tyro Hama Cortis Merces Sector Ala Mars Sypho Tergum Oliva Plebs Pallor Mora Frenum Uncus Spicula Saltus Scena Vestis Moles Bidens Tibicen Urna Ostrum Comes The sides, which touch the vertical plane in the first position, are respectively, in _a c d_ Moena, in _c d a_ Syce, in _d a c_ Alvus. Take the shape Urna, Ostrum, Moles, Saltus, Scena, Sypho, Remus, Aer, Tyro. This gives in _a c d_ the projection: Urna Moena, Ostrum Moena, Moles Moena, Saltus Moena, Scena Moena, Vestis Moena. (If the different positions of the cube are not well known, it is best to have a list of the names before one, but in every case the block should also be built, as well as the names used.) The same shape in the position _c d a_ is, of course, expressed in the same words, but it has a different appearance. The front face consists of the Syces of Saltus Sypho Remus Moles Plebs Hama Urna Frenum Sector And taking the shape we find we have Urna, and we know that Ostrum lies behind Urna, and does not come in; next we have Moles, Saltus, and we know that Scena lies behind Saltus and does not come in; lastly, we have Sypho and Remus, and we know that Aer and Tyro are in the Y direction from Remus, and so do not come in. Hence, altogether the projection will consist only of the Syces of Urna, Moles, Saltus, Sypho, and Remus. Next, taking the position _d a c_, the cubes in the front face have their Alvus sides against the plane, and are: Sector Ala Mars Frenum Uncus Spicula Urna Ostrum Comes And, taking the shape, we find Urna, Ostrum; Moles and Saltus are hidden by Urna, Scena is behind Ostrum, Sypho gives Frenum, Remus gives Sector, Aer gives Ala, and Tyro gives Mars. All these are Alvus sides.