Subscribe to Hydraulic Public Calendar
To see the Hydraulic calendar
log into your email via a browser.
Select Settings from under your name on the far right
Select Folders to Sync from the column on the Left of the settings page.
Check mark the CalDAV/CardDAV item called Hydraulic from the top box.
In Thunderbird
Select the Calendar icon from the Left side of the panel
Select New Calendar from the bottom of the next page.
Select On the Network -> Next
enter your email address in username
and
https://mail.masondynamics.com in the location.
Select Find Calendars
Select the calendars you want to view