| 摘要 |
<p>551,380. Building blocks &c. BUNTON, S., CRAWBORD, W., and PATERSON, J. K. Aug. 19, 1941, No. 10538. [Class 87 (i)] Building blocks, sheets &c. are composed of cellulosic or other fibrous matter such as wood fibres bonded together into blocks &c. e.g. with 'cement and provided on any or all faces with an asphaltic surfacing of appreciable thickness bonded to the blocks &c. to form an impervious hard layer.</p> |
