If the blocks are original, they might just be poor-quality cinder blocks. But as noseall said, many modern building blocks are quite soft and friable - don't see you have a problem.
Like others, I didn't understand about a large part of the weight of the house resting on them.
The proportion of the weight of the house resting on one block will be very low; if the blocks were that bad, the house would not have stood for 100 years. If it's not damp, don't worry about it.
Like others, I didn't understand about a large part of the weight of the house resting on them.
The proportion of the weight of the house resting on one block will be very low; if the blocks were that bad, the house would not have stood for 100 years. If it's not damp, don't worry about it.