The speed limit for orthogonal ships in this rule is definitely faster than c/3. Here's a partial for a 2c/5 ship:
Code: Select all
x = 34, y = 24, rule = B3478/S15678
6bob2o2bo3b2o3bo2b2obo$7b2o2b3o2b2o2b3o2b2o$7bobob2o3b2o3b2obobo$4bobo
b3o5b2o5b3obobo$6bo5bo2b4o2bo5bo$5b3o7b4o7b3o$5b3obob2ob6ob2obob3o$5bo
3bobo3b4o3bobo3bo$3b4obo5bob2obo5bob4o$3bo5bo3b2ob2ob2o3bo5bo$2b3ob3ob
14ob3ob3o$bo2b5o6bo2bo6b5o2bo$2bo2b4o4b2ob2ob2o4b4o2bo$ob2obo8bo4bo8bo
b2obo$2b3o3bo3b2o6b2o3bo3b3o$2b2ob3o3b2obo4bob2o3b3ob2o$ob2ob3o3bo3bo
2bo3bo3b3ob2obo$2o2b4o6bo4bo6b4o2b2o$b5obo6bo4bo6bob5o$2b2o4bo4b2ob2ob
2o4bo4b2o$3b3o3bo4bo4bo4bo3b3o$5b2o4bob2o4b2obo4b2o$6bo2b6o4b6o2bo$7bo
7b4o7bo!
I would be very surprised if c/2 is actually impossible in this rule. Here are two ships in nearby rules which suggest c/2 is possible:
c/2, p4, works in B34/S15 - B3478/S1578
Code: Select all
x = 13, y = 9, rule = B3478/S1578
bo9bo$bo9bo$3bo5bo$o11bo$o3bo3bo3bo$2bo7bo$bobo2bo2bobo$3bob3obo$5b3o!
c/2, p2, works in B34/S156 - B3478/S1568
Code: Select all
x = 23, y = 14, rule = B3478/S1568
7bo7bo$7b2o5b2o$7b2o5b2o$8b3ob3o$9bo3bo$8b2obob2o$5b2ob2o3b2ob2o$5b2ob
o5bob2o$2b2o15b2o$o2bo2bo9bo2bo2bo$bob3o11b3obo$3b4obobobobob4o$4b3ob
3ob3ob3o$8b3ob3o!
So it appears to be the combination of B3 and S167 without any of S0, S2, S3 or S4 which causes the apparent absence of c/2 ships. Adding one of these in seems to allow ships in a fair few other nearby rules:
c/2, p2, with S1467
Code: Select all
x = 15, y = 5, rule = B34/S1467
5b2ob2o$2o2bo5bo2b2o$bo2bobobobo2bo$bobobobobobobo$3bo3bo3bo!
c/2, p2, with S1367
Code: Select all
x = 23, y = 11, rule = B3/S1367
9bo3bo$3b2o4b2ob2o4b2o$bo7b2ob2o7bo$b2o4b2o5b2o4b2o$2bo5b2o3b2o5bo$2b
2o2bo9bo2b2o$3b3obo2bobo2bob3o$4bobo3bobo3bobo$2bo5b2obob2o5bo$3ob2ob
2ob3ob2ob2ob3o$bo3b2o9b2o3bo!
If it does exist, I'm sure a c/2 ship in this rule will be very large, but I don't believe it's impossible.
And now for something completely different - a 2c/3 signal supported by a p2 wick:
Code: Select all
x = 60, y = 20, rule = B3478/S15678:T60,20
5$47bo$45b2o$44bo4bo$43b2o2bo5b2o$2o2b2o2b2o2b2o2b2o2b2o2b2o2b2o2b2o2b
2o2b4ob5obob2o2bo$2b2o2b2o2b2o2b2o2b2o2b2o2b2o2b2o2b2o2b2o2b8obobo2bob
2o$43b2o3bobobo$47bo!