Abstract: A vacuum-tight, nonmetallic hollow article is fabricated from composite material of fibers in a resin matrix. The article has a closed end, and is laid up from sheets of the composite material and end pieces to form the closed end. The layers are mechanically worked and debulked repeatedly during layup between the addition of successive layers, to remove irregularities that can cause vacuum leaks. The joints between the sheets applied to the sidewalls and the end pieces are mechanically worked to effect a vacuum-tight seal, and the joints are staggered as between succeeding layers for strength and integrity. The laid up and debulked piece is finally cured.

Abstract: Apparatus for making biomagnetic measurements includes a biomagnetometer for measuring magnetic fields produced by the body and an electromagnetic location measurement and recording system for automatically determining the location of the portion of the body from which the magnetic signals are being gathered. The electromagnetic location recording system permits establishing a real time body frame of reference with respect to the biomagnetometer, so that biomagnetic signals can be correlated directly with body location and structure. The electromagnetic location recording system may be operated continuously at radiation wavelengths which do not interfere with the taking of data, or intermittently with the taking of biomagnetic data, to avoid interference with the measured values of the biomagnetic data.

Abstract: A vacuum-tight nonmetallic Dewar component is fabricated from composite material of nonmagnetic fibers in a resin matrix. The component is cylindrical with a closed end, and is laid up from sheets of the composite material and circles cut from the sheets to form the closed end. The layers are mechanically worked and debulked repeatedly during layup between the addition of successive layers, to remove irregularities that can cause vacuum leaks. The joints between the sheets applied to the cylindrical surface and the circular end pieces are mechanically worked to effect a vacuum-tight seal, and the joints are staggered as between succeeding layers for strength and integrity. The laid up and debulked piece is finally cured.