you've got them both on the same subnet (172.16.0.1 & .2, with mask 255.255.255.252), which works..
did you set the router/gateway for either one? you need to assign a gateway ('router') setting for each as well..
my normal mehtod for this is to set one systems IP in the gateway as well (ie.,in your situation, setting the machine with 172.16.0.1 as the gateway ip address on BOTH machines), because then BOTH machines will look at that machine for ip traffic...
and your mask doesn't have to be that tight--255.255.255.0 will work perfectly well...