as the topmost clung to the ivy

[SuprunP]

Their pupils - the sparrows, as it were - of Gormenghast were racing to the vast red-sandstone yard - a yard surrounded on all sides by high ivy-covered walls of the same stone. [...] Many a boy had sobbed against these walls; many a knuckle been bruised as a head flicked sideways from the blow. Many a child had fought his way back into the open yard with bloody mouth, and a thousand swaying pyramids of boys had tottered and collapsed as the topmost clung to the ivy.
(M. Peake; Gormenghast)

Is it describing a great many boys who fell trying to climb the walls by means of the ivy and the few topmost, as it were, who achieved the summit?

Thanks.

 

[exgerman]

The pyramid of boys collapsed, but the one at the apex of the pyramid (the topmost boy) was left in mid air, holding on to the ivy.

Such pyramids were attempted thousands of times.

 

[ewie]

The boys were forming human pyramids (but probably bigger than this, as they swayed): all the bottom layers collapsed leaving just the top one clinging to the ivy

 

[SuprunP]

Thank you exgerman and ewie!