diff --git a/strudel.mjs b/strudel.mjs
index 8770728f..36684df9 100644
--- a/strudel.mjs
+++ b/strudel.mjs
@@ -558,11 +558,15 @@ function stack(...pats) {
 function slowcat(...pats) {
     // Concatenation: combines a list of patterns, switching between them
     // successively, one per cycle.
-    // (currently behaves slightly differently from Tidal)
     pats = pats.map(reify)
-    var query = function(span) {
-        var pat = pats[Math.floor(span.begin) % pats.length]
-        return pat.query(span)
+    const query = function(span) {
+        const pat_n = Math.floor(span.begin) % pats.length
+        const pat = pats[pat_n]
+        // A bit of maths to make sure that cycles from constituent patterns aren't skipped.
+        // For example if three patterns are slowcat-ed, the fourth cycle of the result should 
+        // be the second (rather than fourth) cycle from the first pattern.
+        const offset = span.begin.floor().sub(span.begin.div(pats.length).floor())
+        return pat.withEventTime(t => t.add(offset)).query(span.withTime(t => t.sub(offset)))
     }
     return new Pattern(query)._splitQueries()
 }
diff --git a/test/pattern.test.mjs b/test/pattern.test.mjs
index 21f19948..e2183b37 100644
--- a/test/pattern.test.mjs
+++ b/test/pattern.test.mjs
@@ -121,13 +121,15 @@ describe('Pattern', function() {
   })
   describe('slowcat()', function () {
     it('Can concatenate things slowly', function () {
-      assert.deepStrictEqual(slowcat(pure("a"), pure("b")).firstCycle.map(x => x.value), ["a"])
-      assert.deepStrictEqual(slowcat(pure("a"), pure("b"))._early(1).firstCycle.map(x => x.value), ["b"])
+      assert.deepStrictEqual(slowcat("a", "b").firstCycle.map(x => x.value), ["a"])
+      assert.deepStrictEqual(slowcat("a", "b")._early(1).firstCycle.map(x => x.value), ["b"])
+      assert.deepStrictEqual(slowcat("a", slowcat("b", "c"))._early(1).firstCycle.map(x => x.value), ["b"])
+      assert.deepStrictEqual(slowcat("a", slowcat("b", "c"))._early(3).firstCycle.map(x => x.value), ["c"])
     })
   })
   describe('rev()', function () {
     it('Can reverse things', function () {
-      assert.deepStrictEqual(fastcat(pure("a"), pure("b"), pure("c")).rev().firstCycle.sort((a,b) => a.part.begin.sub(b.part.begin)).map(a => a.value), ["c", "b","a"])
+      assert.deepStrictEqual(fastcat("a","b","c").rev().firstCycle.sort((a,b) => a.part.begin.sub(b.part.begin)).map(a => a.value), ["c", "b","a"])
     })
   })
   // describe('sequence()', () => {