Siphnos/Euvoia was a very small passenger ship that was doing mostly the Argosaronikos service.
She appears in Harlaftis' book and is listed as a 87-ton passenger built in 1883. Yes, you read correctly, 87-tons.
She belonged to the Serprieri Line, a small shiiping company active in the late 1880s as shown below
1892 Baedeker4 1892.JPG
Source: Baedeker 1892
And here is a small article about her from the newspapers of March 15, 1898 showing her bad conditions... Stories like this continued for the next 70 years!
18980315 Serpierhs.JPG