Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo showing close up of glass optical flat in case. Photographed label reads: “Glass optical flat. Made by Natural Philosophy Laboratory. Melbourne University. Certificate Number 18. Accuracy of surface, flat within .000,001 (unmarked surface). Accuracy of surface, within .000,002 inch (marked) “use other side”. A photograh in Cd red light of the interference fringes of this flat when placed on a standard glass flat is shown above. Initials: [signature]. Tests made by: [VDH signature]. Certificate issued by T.H.L. Date: Feb 19th 1941.In ink on lower left hand corner : “17”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of E.R. Johnson using equipment.In ink on lower left hand corner : “18”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of Notman working on graphic art.In ink on lower left hand corner : “19”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of E.R.Johnson testing fused sandwiched plate glass in a polarimeter. N.B. As at time of writing it is not certain that the “man” pictured in nos. 147 and 149 is the same individual as pictured in no 140. (EGM. 11/11/99)In ink on lower left hand corner : “20”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of R.L.Abbey looking through telescope of optical spectrometer..In ink on lower left hand corner : “21”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo shows Eric Burhop operating an optical pyrometer ....with possibly a vacuum furnace?In ink on lower left hand corner : “22”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of Optical Munitions Panel meeting (September 1943) of 11 members: L to R: Lt. Col. G.H. Adams; G.H. Briggs; Mr (Sr) Richard v.d.R. Woolly; E.O. Hercus; H.J. Frost; Prof. Kerr Grant (S.A.); Prof. T.H. Laby; Harrigan; J.S. Rogers; Prof. A.D. Ross (W.A.); Prof. T. McAuley (Tas)In ink on lower left hand corner : “23”

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of hands operating glass cutter, producing rectangular strips in preparation for experimental fusing of glass “sandwiches” into optical blocks. Same photo as 265In ink on lower left hand corner : “24”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo showing four assorted optical prisms on a black background. A fifth specimen shows a sandwich glass “prism” assembly prior to cutting and polishing. In ink on lower left hand corner : “25”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of Bob Caldwell cutting through glass “sandwich” using a diamond saw.In ink on lower left hand corner : “26”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of man, possibly Eric Johnson, assembling glass “sandwich” prior to fusing. N.B. As at time of writing it is not certain that the “man” pictured in nos. 147 and 149 is the same individual as pictured in no 140. (EGM. 11/11/99) Same photo as Reg No. 268In ink on lower left hand corner : “27”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of Peter Law and A.C. Goodwin examining optical glass specimens.In ink on lower left hand corner : “28”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of man, possibly E. R. Johnson, examining rectangular glass “sandwich” block in light. N.B. As at time of writing it is not certain that the “man” pictured in nos. 147 and 149 is the same individual as pictured in no 140. (EGM. 11/11/99)In ink on lower left hand corner : “29”.

Part of a series entitled “Optical Munitions - School of Natural Philosophy, 1942-1945”. Black and white photo of J.L. Richardson and -- Dean using an optical bench to test a lens. Lab books are also visible.In ink on lower left hand corner : “30”.

Small cylindrical metal rod with diamond point embedded at one end and a brass circle with 50 divisions and a pointer affixed at the other end to define the orientation of the rod/diamond point. Presumably used with one of the Grayson or Stone engines.On face: “0 10 20 30 40”

Glass rectangular slab stored in brown cardboard box.?? Stamped on back of box: “ExD 40 3453A ECLORTRA” (this may be unrelated)

A microscope slide 3-1/2 in. x 1-1/2 in. to which is cemented a glass rectangle 1-1/2 in. x 1 in. and marked by Grayson as “1 inch”. Possibly a “standard inch” for use on a comparator? (Not very important)Pink label: “Inch”

Black and white print of multiple beam interference fringes showing depth of etching

Black and white print of multiple beam interference fringes showing depth of etching

Black and white print of multiple beam interference fringes showing depth of etching

Black and white print of multiple beam interference fringes showing depth of etching

Rectangular clear glass plate.

5 glass clear thin slides each with yellow stained circular specimens (111.1 to 111.5) 1 clear blank slide (111.6)

Refer to Cat No 141 for full details. Black and white photo shows Ray Abbey looking through telescope of optical spectrometer. Duplicate copy of Cat no 141; in OMP Album Vol 2 #21. In ink on lower left hand corner: “21”. Inscribed on back in pencil: “No. 21 R.L.ABBEY”

Part of a series of optical munition snapshots 1940-1947. Refer to Cat No 133 for full details. Black and white photo shows Fred Caldwell looking through optical instrument. Duplicate copy of Cat no 133; in OMP Album Vol 1 #13.In ink on lower left hand corner : “13”. Inscribed on back in pencil: “No. 13 FRED CALDWELL”

Part of a series of optical munition snapshots 1940-1947. Refer to Cat No 146 for full details. Black and white photo shows Bob Caldwell cutting with a diamond saw through a sandwich of optical glass . Duplicate copy of Cat no 146; in OMP Album Vol 2 #26. In ink on lower left hand corner : “26”. Inscribed on back in pencil: “No. 26 ROBERT CALDWELL”

Part of a series of optical munition snapshots 1940-1947. Refer to Cat No 134 for full details. Black and white photo of optical instrument “director”. Duplicate copy of Cat no 134; in OMP Album Vol 1 #14.In ink on lower left hand corner : “14”. Inscribed on back in pencil: “No. 14”

Part of a series of optical munition snapshots 1940-1947. Refer to Cat No 138 for full details. Black and white photo shows E R Johnson performing (presumably) test of optical specimen. Duplicate copy of Cat no 138; in OMP Album Vol 1 #18 .In ink on lower left hand corner : “18”. Inscribed on back in pencil: “No. 18 E.R. JOHNSON”

Part of a series of optical munition snapshots 1940-1947. Refer to Cat No 137 for full details. Black and white photo of optical flat in de luxe case with certificate: “GLASS OPTICAL FLAT, made by Natural Philosophy Laboratory, Melbourne University” Number 18. Accuracy of surface flat within .000,001 inch .... Issued by (signd) T.H.L. Feb 19, 1941. Duplicate copy of Cat no 137; in OMP Album Vol 1 #17.In ink on lower left hand corner : “17”. Inscribed on back in pencil: “No. 17”