Although the firm was formed in 1875, the origin of its patent horticultural structures dates back 16 years to 1859 when Thomas Messenger submitted the first of three patents applications. This earliest patent was by far the most important and introduced three concepts that were to prove effective for around the next 100 years:
- The use of an iron muntin, sitting on the sill, supporting the eave plate, principal rafter and front lights.
- The use much lighter rafters supported by tensions rods connecting the muntin to the ridge spandrel.
- Continuous opening front or top lights along the complete length of the structure.
When Thomas Messenger sold his horticultural and heating business in 1875, he also included the intellectual property rights to these three horticultural building construction patents. Over the following decades the design was refined and adapted, although the principals of the initial patent remained essentially inviolate.
The design of the iron muntin was modified to accommodate the change in the supports for the front light opening apparatus, moving from a continuous chain to a spring-lever mechanism. The continuous chain operated by use of a flat bar, whilst the spring-lever used a circular profiled rod. Initially only available in one size, the muntin was eventually offered in four height sizes, reflecting the height of the front light. The most recognizable change was adjacent to the eave plate and rafter support; this originally appeared utilitarian, later becoming more ‘artistic’ using a “sun ray” style motif.
Similarly the spandrels and brackets evolved both in number and design sophistication, also adopting the “sun ray” style motif.
The most significant change was the move away from a continuous chain operated top and front light to a spring lever balanced top and front light opening mechanism. This was the subject of an 1895 patent (No. 21,677), entitled “Improvements in Apparatus or Appliances for Raising or Opening Hinged Ventilators or Lights of Greenhouses and other Buildings”; although it was being offered for sale several years prior to the patent application submission. The most noticeable changes were that of the spring level, which evolved in both design and size between the 1890s and 1920; again adopting the “sun ray” style motif.