How. do I combine variables into one Matrix?

I have about 25 stations with the same variable. I want to extract the variable from each file and combine them into one matrix, so that each column in the matrix is one station. The code below is what ive attempted but failed:

direc=dir('*.mat');
station=[];
for i=length(direc)
    load(direc(i).name);
    station=[station;zonal1.station];
end

Answer 1

[Walter Roberson]

station(:, i) = zonal1.station(:);

This will fail if the data is not all the same size.