.picture{
  float: left;
  margin-right: 100px;
  height: 500px;
}

.picture-mid {
  height: 700px;
  margin-right: 100px;
}
/*
.picture-tall {
  height: 900px;
  float: none;
  display: block;
  margin-left: auto;
  margin-right: auto;
  width: 40%;
  padding-right: 200px;
  overflow: auto;
}*/

.picture-tall {
  height: 900px;
  margin-left: 250px;
  /*float: none;
  display: block;
  margin-left: auto;
  margin-right: auto;
  width: 40%;
  padding-right: 200px;
  overflow: auto;*/
}