The reason you did not see an appointment option when submitting your requests is probably that you did not have an appointment scheduled for the system to find. To schedule an appointment, log in to your Portal1791 account and click on the “Appointments” button* in the top ribbon. On the next screen, click "New Appointment", select your date(s) on the calendar and then the length and start time, then click “Create Appointment.”
Now, go back to the online collection guide, select all of the pieces you want to view, and click the red “Continue” button at the bottom of the screen. When the request form appears, select “Request for Library Use”, enter your Portal1791 username and click “Find”, then you should see your scheduled appointment(s) in the drop-down*. Select your appointment then scroll down and click “Submit Request.”